[Python-checkins] r43159 - python/trunk/Misc/HISTORY python/trunk/Misc/NEWS
anthony.baxter
python-checkins at python.org
Mon Mar 20 07:30:53 CET 2006
Author: anthony.baxter
Date: Mon Mar 20 07:30:41 2006
New Revision: 43159
Modified:
python/trunk/Misc/HISTORY
python/trunk/Misc/NEWS
Log:
moved older releases into HISTORY
Modified: python/trunk/Misc/HISTORY
==============================================================================
--- python/trunk/Misc/HISTORY (original)
+++ python/trunk/Misc/HISTORY Mon Mar 20 07:30:41 2006
@@ -8,6 +8,5293 @@
======================================================================
+What's New in Python 2.4 final?
+===============================
+
+*Release date: 30-NOV-2004*
+
+Core and builtins
+-----------------
+
+- Bug 875692: Improve signal handling, especially when using threads, by
+ forcing an early re-execution of PyEval_EvalFrame() "periodic" code when
+ things_to_do is not cleared by Py_MakePendingCalls().
+
+
+What's New in Python 2.4 (release candidate 1)
+==============================================
+
+*Release date: 18-NOV-2004*
+
+Core and builtins
+-----------------
+
+- Bug 1061968: Fixes in 2.4a3 to address thread bug 1010677 reintroduced
+ the years-old thread shutdown race bug 225673. Numeric history lesson
+ aside, all bugs in all three reports are fixed now.
+
+
+Library
+-------
+
+- Bug 1052242: If exceptions are raised by an atexit handler function an
+ attempt is made to execute the remaining handlers. The last exception
+ raised is re-raised.
+
+- ``doctest``'s new support for adding ``pdb.set_trace()`` calls to
+ doctests was broken in a dramatic but shallow way. Fixed.
+
+- Bug 1065388: ``calendar``'s ``day_name``, ``day_abbr``, ``month_name``,
+ and ``month_abbr`` attributes emulate sequences of locale-correct
+ spellings of month and day names. Because the locale can change at
+ any time, the correct spelling is recomputed whenever one of these is
+ indexed. In the worst case, the index may be a slice object, so these
+ recomputed every day or month name each time they were indexed. This is
+ much slower than necessary in the usual case, when the index is just an
+ integer. In that case, only the single spelling needed is recomputed
+ now; and, when the index is a slice object, only the spellings needed
+ by the slice are recomputed now.
+
+- Patch 1061679: Added ``__all__`` to pickletools.py.
+
+Build
+-----
+
+- Bug 1034277 / Patch 1035255: Remove compilation of core against CoreServices
+ and CoreFoundation on OS X. Involved removing PyMac_GetAppletScriptFile()
+ which has no known users. Thanks Bob Ippolito.
+
+C API
+-----
+
+- The PyRange_New() function is deprecated.
+
+
+What's New in Python 2.4 beta 2?
+================================
+
+*Release date: 03-NOV-2004*
+
+License
+-------
+
+The Python Software Foundation changed the license under which Python
+is released, to remove Python version numbers. There were no other
+changes to the license. So, for example, wherever the license for
+Python 2.3 said "Python 2.3", the new license says "Python". The
+intent is to make it possible to refer to the PSF license in a more
+durable way. For example, some people say they're confused by that
+the Open Source Initiative's entry for the Python Software Foundation
+License::
+
+ http://www.opensource.org/licenses/PythonSoftFoundation.php
+
+says "Python 2.1.1" all over it, wondering whether it applies only
+to Python 2.1.1.
+
+The official name of the new license is the Python Software Foundation
+License Version 2.
+
+Core and builtins
+-----------------
+
+- Bug #1055820 Cyclic garbage collection was not protecting against that
+ calling a live weakref to a piece of cyclic trash could resurrect an
+ insane mutation of the trash if any Python code ran during gc (via
+ running a dead object's __del__ method, running another callback on a
+ weakref to a dead object, or via any Python code run in any other thread
+ that managed to obtain the GIL while a __del__ or callback was running
+ in the thread doing gc). The most likely symptom was "impossible"
+ ``AttributeError`` exceptions, appearing seemingly at random, on weakly
+ referenced objects. The cure was to clear all weakrefs to unreachable
+ objects before allowing any callbacks to run.
+
+- Bug #1054139 _PyString_Resize() now invalidates its cached hash value.
+
+Extension Modules
+-----------------
+
+- Bug #1048870: the compiler now generates distinct code objects for
+ functions with identical bodies. This was producing confusing
+ traceback messages which pointed to the function where the code
+ object was first defined rather than the function being executed.
+
+Library
+-------
+
+- Patch #1056967 changes the semantics of Template.safe_substitute() so that
+ no ValueError is raised on an 'invalid' match group. Now the delimiter is
+ returned.
+
+- Bug #1052503 pdb.runcall() was not passing along keyword arguments.
+
+- Bug #902037: XML.sax.saxutils.prepare_input_source() now combines relative
+ paths with a base path before checking os.path.isfile().
+
+- The whichdb module can now be run from the command line.
+
+- Bug #1045381: time.strptime() can now infer the date using %U or %W (week of
+ the year) when the day of the week and year are also specified.
+
+- Bug #1048816: fix bug in Ctrl-K at start of line in curses.textpad.Textbox
+
+- Bug #1017553: fix bug in tarfile.filemode()
+
+- Patch #737473: fix bug that old source code is shown in tracebacks even if
+ the source code is updated and reloaded.
+
+Build
+-----
+
+- Patch #1044395: --enable-shared is allowed in FreeBSD also.
+
+What's New in Python 2.4 beta 1?
+================================
+
+*Release date: 15-OCT-2004*
+
+Core and builtins
+-----------------
+
+- Patch #975056: Restartable signals were not correctly disabled on
+ BSD systems. Consistently use PyOS_setsig() instead of signal().
+
+- The internal portable implementation of thread-local storage (TLS), used
+ by the ``PyGILState_Ensure()``/``PyGILState_Release()`` API, was not
+ thread-correct. This could lead to a variety of problems, up to and
+ including segfaults. See bug 1041645 for an example.
+
+- Added a command line option, -m module, which searches sys.path for the
+ module and then runs it. (Contributed by Nick Coghlan.)
+
+- The bytecode optimizer now folds tuples of constants into a single
+ constant.
+
+- SF bug #513866: Float/long comparison anomaly. Prior to 2.4b1, when
+ an integer was compared to a float, the integer was coerced to a float.
+ That could yield spurious overflow errors (if the integer was very
+ large), and to anomalies such as
+ ``long(1e200)+1 == 1e200 == long(1e200)-1``. Coercion to float is no
+ longer performed, and cases like ``long(1e200)-1 < 1e200``,
+ ``long(1e200)+1 > 1e200`` and ``(1 << 20000) > 1e200`` are computed
+ correctly now.
+
+Extension modules
+-----------------
+
+- ``collections.deque`` objects didn't play quite right with garbage
+ collection, which could lead to a segfault in a release build, or
+ an assert failure in a debug build. Also, added overflow checks,
+ better detection of mutation during iteration, and shielded deque
+ comparisons from unusual subclass overrides of the __iter__() method.
+
+Library
+-------
+
+- Patch 1046644: distutils build_ext grew two new options - --swig for
+ specifying the swig executable to use, and --swig-opts to specify
+ options to pass to swig. --swig-opts="-c++" is the new way to spell
+ --swig-cpp.
+
+- Patch 983206: distutils now obeys environment variable LDSHARED, if
+ it is set.
+
+- Added Peter Astrand's subprocess.py module. See PEP 324 for details.
+
+- time.strptime() now properly escapes timezones and all other locale-specific
+ strings for regex-specific symbols. Was breaking under Japanese Windows when
+ the timezone was specified as "Tokyo (standard time)".
+ Closes bug #1039270.
+
+- Updates for the email package:
+
+ + email.Utils.formatdate() grew a 'usegmt' argument for HTTP support.
+ + All deprecated APIs that in email 2.x issued warnings have been removed:
+ _encoder argument to the MIMEText constructor, Message.add_payload(),
+ Utils.dump_address_pair(), Utils.decode(), Utils.encode()
+ + New deprecations: Generator.__call__(), Message.get_type(),
+ Message.get_main_type(), Message.get_subtype(), the 'strict' argument to
+ the Parser constructor. These will be removed in email 3.1.
+ + Support for Python earlier than 2.3 has been removed (see PEP 291).
+ + All defect classes have been renamed to end in 'Defect'.
+ + Some FeedParser fixes; also a MultipartInvariantViolationDefect will be
+ added to messages that claim to be multipart but really aren't.
+ + Updates to documentation.
+
+- re's findall() and finditer() functions now take an optional flags argument
+ just like the compile(), search(), and match() functions. Also, documented
+ the previously existing start and stop parameters for the findall() and
+ finditer() methods of regular expression objects.
+
+- rfc822 Messages now support iterating over the headers.
+
+- The (undocumented) tarfile.Tarfile.membernames has been removed;
+ applications should use the getmember function.
+
+- httplib now offers symbolic constants for the HTTP status codes.
+
+- SF bug #1028306: Trying to compare a ``datetime.date`` to a
+ ``datetime.datetime`` mistakenly compared only the year, month and day.
+ Now it acts like a mixed-type comparison: ``False`` for ``==``,
+ ``True`` for ``!=``, and raises ``TypeError`` for other comparison
+ operators. Because datetime is a subclass of date, comparing only the
+ base class (date) members can still be done, if that's desired, by
+ forcing using of the approprate date method; e.g.,
+ ``a_date.__eq__(a_datetime)`` is true if and only if the year, month
+ and day members of ``a_date`` and ``a_datetime`` are equal.
+
+- bdist_rpm now supports command line options --force-arch,
+ {pre,post}-install, {pre,post}-uninstall, and
+ {prep,build,install,clean,verify}-script.
+
+- SF patch #998993: The UTF-8 and the UTF-16 stateful decoders now support
+ decoding incomplete input (when the input stream is temporarily exhausted).
+ ``codecs.StreamReader`` now implements buffering, which enables proper
+ readline support for the UTF-16 decoders. ``codecs.StreamReader.read()``
+ has a new argument ``chars`` which specifies the number of characters to
+ return. ``codecs.StreamReader.readline()`` and
+ ``codecs.StreamReader.readlines()`` have a new argument ``keepends``.
+ Trailing "\n"s will be stripped from the lines if ``keepends`` is false.
+
+- The documentation for doctest is greatly expanded, and now covers all
+ the new public features (of which there are many).
+
+- ``doctest.master`` was put back in, and ``doctest.testmod()`` once again
+ updates it. This isn't good, because every ``testmod()`` call
+ contributes to bloating the "hidden" state of ``doctest.master``, but
+ some old code apparently relies on it. For now, all we can do is
+ encourage people to stitch doctests together via doctest's unittest
+ integration features instead.
+
+- httplib now handles ipv6 address/port pairs.
+
+- SF bug #1017864: ConfigParser now correctly handles default keys,
+ processing them with ``ConfigParser.optionxform`` when supplied,
+ consistent with the handling of config file entries and runtime-set
+ options.
+
+- SF bug #997050: Document, test, & check for non-string values in
+ ConfigParser. Moved the new string-only restriction added in
+ rev. 1.65 to the SafeConfigParser class, leaving existing
+ ConfigParser & RawConfigParser behavior alone, and documented the
+ conditions under which non-string values work.
+
+Build
+-----
+
+- Building on darwin now includes /opt/local/include and /opt/local/lib for
+ building extension modules. This is so as to include software installed as
+ a DarwinPorts port <http://darwinports.opendarwin.org/>
+
+- pyport.h now defines a Py_IS_NAN macro. It works as-is when the
+ platform C computes true for ``x != x`` if and only if X is a NaN.
+ Other platforms can override the default definition with a platform-
+ specific spelling in that platform's pyconfig.h. You can also override
+ pyport.h's default Py_IS_INFINITY definition now.
+
+C API
+-----
+
+- SF patch 1044089: New function ``PyEval_ThreadsInitialized()`` returns
+ non-zero if PyEval_InitThreads() has been called.
+
+- The undocumented and unused extern int ``_PyThread_Started`` was removed.
+
+- The C API calls ``PyInterpreterState_New()`` and ``PyThreadState_New()``
+ are two of the very few advertised as being safe to call without holding
+ the GIL. However, this wasn't true in a debug build, as bug 1041645
+ demonstrated. In a debug build, Python redirects the ``PyMem`` family
+ of calls to Python's small-object allocator, to get the benefit of
+ its extra debugging capabilities. But Python's small-object allocator
+ isn't threadsafe, relying on the GIL to avoid the expense of doing its
+ own locking. ``PyInterpreterState_New()`` and ``PyThreadState_New()``
+ call the platform ``malloc()`` directly now, regardless of build type.
+
+- PyLong_AsUnsignedLong[Mask] now support int objects as well.
+
+- SF patch #998993: ``PyUnicode_DecodeUTF8Stateful`` and
+ ``PyUnicode_DecodeUTF16Stateful`` have been added, which implement stateful
+ decoding.
+
+Tests
+-----
+
+- test__locale ported to unittest
+
+Mac
+---
+
+- ``plistlib`` now supports non-dict root objects. There is also a new
+ interface for reading and writing plist files: ``readPlist(pathOrFile)``
+ and ``writePlist(rootObject, pathOrFile)``
+
+Tools/Demos
+-----------
+
+- The text file comparison scripts ``ndiff.py`` and ``diff.py`` now
+ read the input files in universal-newline mode. This spares them
+ from consuming a great deal of time to deduce the useless result that,
+ e.g., a file with Windows line ends and a file with Linux line ends
+ have no lines in common.
+
+
+What's New in Python 2.4 alpha 3?
+=================================
+
+*Release date: 02-SEP-2004*
+
+Core and builtins
+-----------------
+
+- SF patch #1007189: ``from ... import ...`` statements now allow the name
+ list to be surrounded by parentheses.
+
+- Some speedups for long arithmetic, thanks to Trevor Perrin. Gradeschool
+ multiplication was sped a little by optimizing the C code. Gradeschool
+ squaring was sped by about a factor of 2, by exploiting that about half
+ the digit products are duplicates in a square. Because exponentiation
+ uses squaring often, this also speeds long power. For example, the time
+ to compute 17**1000000 dropped from about 14 seconds to 9 on my box due
+ to this much. The cutoff for Karatsuba multiplication was raised,
+ since gradeschool multiplication got quicker, and the cutoff was
+ aggressively small regardless. The exponentiation algorithm was switched
+ from right-to-left to left-to-right, which is more efficient for small
+ bases. In addition, if the exponent is large, the algorithm now does
+ 5 bits (instead of 1 bit) at a time. That cut the time to compute
+ 17**1000000 on my box in half again, down to about 4.5 seconds.
+
+- OverflowWarning is no longer generated. PEP 237 scheduled this to
+ occur in Python 2.3, but since OverflowWarning was disabled by default,
+ nobody realized it was still being generated. On the chance that user
+ code is still using them, the Python builtin OverflowWarning, and
+ corresponding C API PyExc_OverflowWarning, will exist until Python 2.5.
+
+- Py_InitializeEx has been added.
+
+- Fix the order of application of decorators. The proper order is bottom-up;
+ the first decorator listed is the last one called.
+
+- SF patch #1005778. Fix a seg fault if the list size changed while
+ calling list.index(). This could happen if a rich comparison function
+ modified the list.
+
+- The ``func_name`` (a.k.a. ``__name__``) attribute of user-defined
+ functions is now writable.
+
+- code_new (a.k.a new.code()) now checks its arguments sufficiently
+ carefully that passing them on to PyCode_New() won't trigger calls
+ to Py_FatalError() or PyErr_BadInternalCall(). It is still the case
+ that the returned code object might be entirely insane.
+
+- Subclasses of string can no longer be interned. The semantics of
+ interning were not clear here -- a subclass could be mutable, for
+ example -- and had bugs. Explicitly interning a subclass of string
+ via intern() will raise a TypeError. Internal operations that attempt
+ to intern a string subclass will have no effect.
+
+- Bug 1003935: xrange() could report bogus OverflowErrors. Documented
+ what xrange() intends, and repaired tests accordingly.
+
+Extension modules
+-----------------
+
+- difflib now supports HTML side-by-side diff.
+
+- os.urandom has been added for systems that support sources of random
+ data.
+
+- Patch 1012740: truncate() on a writeable cStringIO now resets the
+ position to the end of the stream. This is consistent with the original
+ StringIO module and avoids inadvertently resurrecting data that was
+ supposed to have been truncated away.
+
+- Added socket.socketpair().
+
+- Added CurrentByteIndex, CurrentColumnNumber, CurrentLineNumber
+ members to xml.parsers.expat.XMLParser object.
+
+- The mpz, rotor, and xreadlines modules, all deprecated in earlier
+ versions of Python, have now been removed.
+
+Library
+-------
+
+- Patch #934356: if a module defines __all__, believe that rather than using
+ heuristics for filtering out imported names.
+
+- Patch #941486: added os.path.lexists(), which returns True for broken
+ symlinks, unlike os.path.exists().
+
+- the random module now uses os.urandom() for seeding if it is available.
+ Added a new generator based on os.urandom().
+
+- difflib and diff.py can now generate HTML.
+
+- bdist_rpm now includes version and release in the BuildRoot, and
+ replaces - by ``_`` in version and release.
+
+- distutils build/build_scripts now has an -e option to specify the
+ path to the Python interpreter for installed scripts.
+
+- PEP 292 classes Template and SafeTemplate are added to the string module.
+
+- tarfile now generates GNU tar files by default.
+
+- HTTPResponse has now a getheaders method.
+
+- Patch #1006219: let inspect.getsource handle '@' decorators. Thanks Simon
+ Percivall.
+
+- logging.handlers.SMTPHandler.date_time has been removed;
+ the class now uses email.Utils.formatdate to generate the time stamp.
+
+- A new function tkFont.nametofont was added to return an existing
+ font. The Font class constructor now has an additional exists argument
+ which, if True, requests to return/configure an existing font, rather
+ than creating a new one.
+
+- Updated the decimal package's min() and max() methods to match the
+ latest revision of the General Decimal Arithmetic Specification.
+ Quiet NaNs are ignored and equal values are sorted based on sign
+ and exponent.
+
+- The decimal package's Context.copy() method now returns deep copies.
+
+- Deprecated sys.exitfunc in favor of the atexit module. The sys.exitfunc
+ attribute will be kept around for backwards compatibility and atexit
+ will just become the one preferred way to do it.
+
+- patch #675551: Add get_history_item and replace_history_item functions
+ to the readline module.
+
+- bug #989672: pdb.doc and the help messages for the help_d and help_u methods
+ of the pdb.Pdb class gives have been corrected. d(own) goes to a newer
+ frame, u(p) to an older frame, not the other way around.
+
+- bug #990669: os.path.realpath() will resolve symlinks before normalizing the
+ path, as normalizing the path may alter the meaning of the path if it
+ contains symlinks.
+
+- bug #851123: shutil.copyfile will raise an exception when trying to copy a
+ file onto a link to itself. Thanks Gregory Ball.
+
+- bug #570300: Fix inspect to resolve file locations using os.path.realpath()
+ so as to properly list all functions in a module when the module itself is
+ reached through a symlink. Thanks Johannes Gijsbers.
+
+- doctest refactoring continued. See the docs for details. As part of
+ this effort, some old and little- (never?) used features are now
+ deprecated: the Tester class, the module is_private() function, and the
+ isprivate argument to testmod(). The Tester class supplied a feeble
+ "by hand" way to combine multiple doctests, if you knew exactly what
+ you were doing. The newer doctest features for unittest integration
+ already did a better job of that, are stronger now than ever, and the
+ new DocTestRunner class is a saner foundation if you want to do it by
+ hand. The "private name" filtering gimmick was a mistake from the
+ start, and testmod() changed long ago to ignore it by default. If
+ you want to filter out tests, the new DocTestFinder class can be used
+ to return a list of all doctests, and you can filter that list by
+ any computable criteria before passing it to a DocTestRunner instance.
+
+- Bug #891637, patch #1005466: fix inspect.getargs() crash on def foo((bar)).
+
+Tools/Demos
+-----------
+
+- IDLE's shortcut keys for windows are now case insensitive so that
+ Control-V works the same as Control-v.
+
+- pygettext.py: Generate POT-Creation-Date header in ISO format.
+
+Build
+-----
+
+- Backward incompatibility: longintrepr.h now triggers a compile-time
+ error if SHIFT (the number of bits in a Python long "digit") isn't
+ divisible by 5. This new requirement allows simple code for the new
+ 5-bits-at-a-time long_pow() implementation. If necessary, the
+ restriction could be removed (by complicating long_pow(), or by
+ falling back to the 1-bit-at-a-time algorithm), but there are no
+ plans to do so.
+
+- bug #991962: When building with --disable-toolbox-glue on Darwin no
+ attempt to build Mac-specific modules occurs.
+
+- The --with-tsc flag to configure to enable VM profiling with the
+ processor's timestamp counter now works on PPC platforms.
+
+- patch #1006629: Define _XOPEN_SOURCE to 500 on Solaris 8/9 to match
+ GCC's definition and avoid redefinition warnings.
+
+- Detect pthreads support (provided by gnu pth pthread emulation) on
+ GNU/k*BSD systems.
+
+- bug #1005737, #1007249: Fixed several build problems and warnings
+ found on old/legacy C compilers of HP-UX, IRIX and Tru64.
+
+C API
+-----
+
+..
+
+Documentation
+-------------
+
+- patch #1005936, bug #1009373: fix index entries which contain
+ an underscore when viewed with Acrobat.
+
+- bug #990669: os.path.normpath may alter the meaning of a path if
+ it contains symbolic links. This has been documented in a comment
+ since 1992, but is now in the library reference as well.
+
+New platforms
+-------------
+
+- FreeBSD 6 is now supported.
+
+Tests
+-----
+
+..
+
+Windows
+-------
+
+- Boosted the stack reservation for python.exe and pythonw.exe from
+ the default 1MB to 2MB. Stack frames under VC 7.1 for 2.4 are enough
+ bigger than under VC 6.0 for 2.3.4 that deeply recursive progams
+ within the default sys.getrecursionlimit() default value of 1000 were
+ able to suffer undetected C stack overflows. The standard test program
+ test_compiler was one such program. If a Python process on Windows
+ "just vanishes" without a trace, and without an error message of any
+ kind, but with an exit code of 128, undetected stack overflow may be
+ the problem.
+
+Mac
+---
+
+..
+
+
+What's New in Python 2.4 alpha 2?
+=================================
+
+*Release date: 05-AUG-2004*
+
+Core and builtins
+-----------------
+
+- Patch #980695: Implements efficient string concatenation for statements
+ of the form s=s+t and s+=t. This will vary across implementations.
+ Accordingly, the str.join() method is strongly preferred for performance
+ sensitive code.
+
+- PEP-0318, Function Decorators have been added to the language. These are
+ implemented using the Java-style @decorator syntax, like so::
+
+ @staticmethod
+ def foo(bar):
+
+ (The PEP needs to be updated to reflect the current state)
+
+- When importing a module M raises an exception, Python no longer leaves M
+ in sys.modules. Before 2.4a2 it did, and a subsequent import of M would
+ succeed, picking up a module object from sys.modules reflecting as much
+ of the initialization of M as completed before the exception was raised.
+ Subsequent imports got no indication that M was in a partially-
+ initialized state, and the importers could get into arbitrarily bad
+ trouble as a result (the M they got was in an unintended state,
+ arbitrarily far removed from M's author's intent). Now subsequent
+ imports of M will continue raising exceptions (but if, for example, the
+ source code for M is edited between import attempts, then perhaps later
+ attempts will succeed, or raise a different exception).
+
+ This can break existing code, but in such cases the code was probably
+ working before by accident. In the Python source, the only case of
+ breakage discovered was in a test accidentally relying on a damaged
+ module remaining in sys.modules. Cases are also known where tests
+ deliberately provoking import errors remove damaged modules from
+ sys.modules themselves, and such tests will break now if they do an
+ unconditional del sys.modules[M].
+
+- u'%s' % obj will now try obj.__unicode__() first and fallback to
+ obj.__str__() if no __unicode__ method can be found.
+
+- Patch #550732: Add PyArg_VaParseTupleAndKeywords(). Analogous to
+ PyArg_VaParse(). Both are now documented. Thanks Greg Chapman.
+
+- Allow string and unicode return types from .encode()/.decode()
+ methods on string and unicode objects. Added unicode.decode()
+ which was missing for no apparent reason.
+
+- An attempt to fix the mess that is Python's behaviour with
+ signal handlers and threads, complicated by readline's behaviour.
+ It's quite possible that there are still bugs here.
+
+- Added C macros Py_CLEAR and Py_VISIT to ease the implementation of
+ types that support garbage collection.
+
+- Compiler now treats None as a constant.
+
+- The type of values returned by __int__, __float__, __long__,
+ __oct__, and __hex__ are now checked. Returning an invalid type
+ will cause a TypeError to be raised. This matches the behavior of
+ Jython.
+
+- Implemented bind_textdomain_codeset() in locale module.
+
+- Added a workaround for proper string operations in BSDs. str.split
+ and str.is* methods can now work correctly with UTF-8 locales.
+
+- Bug #989185: unicode.iswide() and unicode.width() is dropped and
+ the East Asian Width support is moved to unicodedata extension
+ module.
+
+- Patch #941229: The source code encoding in interactive mode
+ now refers sys.stdin.encoding not just ISO-8859-1 anymore. This
+ allows for non-latin-1 users to write unicode strings directly.
+
+Extension modules
+-----------------
+
+- cpickle now supports the same keyword arguments as pickle.
+
+Library
+-------
+
+- Added new codecs and aliases for ISO_8859-11, ISO_8859-16 and
+ TIS-620
+
+- Thanks to Edward Loper, doctest has been massively refactored, and
+ many new features were added. Full docs will appear later. For now
+ the doctest module comments and new test cases give good coverage.
+ The refactoring provides many hook points for customizing behavior
+ (such as how to report errors, and how to compare expected to actual
+ output). New features include a <BLANKLINE> marker for expected
+ output containing blank lines, options to produce unified or context
+ diffs when actual output doesn't match expectations, an option to
+ normalize whitespace before comparing, and an option to use an
+ ellipsis to signify "don't care" regions of output.
+
+- Tkinter now supports the wish -sync and -use options.
+
+- The following methods in time support passing of None: ctime(), gmtime(),
+ and localtime(). If None is provided, the current time is used (the
+ same as when the argument is omitted).
+ [SF bug 658254, patch 663482]
+
+- nntplib does now allow to ignore a .netrc file.
+
+- urllib2 now recognizes Basic authentication even if other authentication
+ schemes are offered.
+
+- Bug #1001053. wave.open() now accepts unicode filenames.
+
+- gzip.GzipFile has a new fileno() method, to retrieve the handle of the
+ underlying file object (provided it has a fileno() method). This is
+ needed if you want to use os.fsync() on a GzipFile.
+
+- imaplib has two new methods: deleteacl and myrights.
+
+- nntplib has two new methods: description and descriptions. They
+ use a more RFC-compliant way of getting a newsgroup description.
+
+- Bug #993394. Fix a possible red herring of KeyError in 'threading' being
+ raised during interpreter shutdown from a registered function with atexit
+ when dummy_threading is being used.
+
+- Bug #857297/Patch #916874. Fix an error when extracting a hard link
+ from a tarfile.
+
+- Patch #846659. Fix an error in tarfile.py when using
+ GNU longname/longlink creation.
+
+- The obsolete FCNTL.py has been deleted. The builtin fcntl module
+ has been available (on platforms that support fcntl) since Python
+ 1.5a3, and all FCNTL.py did is export fcntl's names, after generating
+ a deprecation warning telling you to use fcntl directly.
+
+- Several new unicode codecs are added: big5hkscs, euc_jis_2004,
+ iso2022_jp_2004, shift_jis_2004.
+
+- Bug #788520. Queue.{get, get_nowait, put, put_nowait} have new
+ implementations, exploiting Conditions (which didn't exist at the time
+ Queue was introduced). A minor semantic change is that the Full and
+ Empty exceptions raised by non-blocking calls now occur only if the
+ queue truly was full or empty at the instant the queue was checked (of
+ course the Queue may no longer be full or empty by the time a calling
+ thread sees those exceptions, though). Before, the exceptions could
+ also be raised if it was "merely inconvenient" for the implementation
+ to determine the true state of the Queue (because the Queue was locked
+ by some other method in progress).
+
+- Bugs #979794 and #980117: difflib.get_grouped_opcodes() now handles the
+ case of comparing two empty lists. This affected both context_diff() and
+ unified_diff(),
+
+- Bug #980938: smtplib now prints debug output to sys.stderr.
+
+- Bug #930024: posixpath.realpath() now handles infinite loops in symlinks by
+ returning the last point in the path that was not part of any loop. Thanks
+ AM Kuchling.
+
+- Bug #980327: ntpath not handles compressing erroneous slashes between the
+ drive letter and the rest of the path. Also clearly handles UNC addresses now
+ as well. Thanks Paul Moore.
+
+- bug #679953: zipfile.py should now work for files over 2 GB. The packed data
+ for file sizes (compressed and uncompressed) was being stored as signed
+ instead of unsigned.
+
+- decimal.py now only uses signals in the IBM spec. The other conditions are
+ no longer part of the public API.
+
+- codecs module now has two new generic APIs: encode() and decode()
+ which don't restrict the return types (unlike the unicode and
+ string methods of the same name).
+
+- Non-blocking SSL sockets work again; they were broken in Python 2.3.
+ SF patch 945642.
+
+- doctest unittest integration improvements:
+
+ o Improved the unitest test output for doctest-based unit tests
+
+ o Can now pass setUp and tearDown functions when creating
+ DocTestSuites.
+
+- The threading module has a new class, local, for creating objects
+ that provide thread-local data.
+
+- Bug #990307: when keep_empty_values is True, cgi.parse_qsl()
+ no longer returns spurious empty fields.
+
+- Implemented bind_textdomain_codeset() in gettext module.
+
+- Introduced in gettext module the l*gettext() family of functions,
+ which return translation strings encoded in the preferred encoding,
+ as informed by locale module's getpreferredencoding().
+
+- optparse module (and tests) upgraded to Optik 1.5a1. Changes:
+
+ - Add expansion of default values in help text: the string
+ "%default" in an option's help string is expanded to str() of
+ that option's default value, or "none" if no default value.
+
+ - Bug #955889: option default values that happen to be strings are
+ now processed in the same way as values from the command line; this
+ allows generation of nicer help when using custom types. Can
+ be disabled with parser.set_process_default_values(False).
+
+ - Bug #960515: don't crash when generating help for callback
+ options that specify 'type', but not 'dest' or 'metavar'.
+
+ - Feature #815264: change the default help format for short options
+ that take an argument from e.g. "-oARG" to "-o ARG"; add
+ set_short_opt_delimiter() and set_long_opt_delimiter() methods to
+ HelpFormatter to allow (slight) customization of the formatting.
+
+ - Patch #736940: internationalize Optik: all built-in user-
+ targeted literal strings are passed through gettext.gettext(). (If
+ you want translations (.po files), they're not included with Python
+ -- you'll find them in the Optik source distribution from
+ http://optik.sourceforge.net/ .)
+
+ - Bug #878453: respect $COLUMNS environment variable for
+ wrapping help output.
+
+ - Feature #988122: expand "%prog" in the 'description' passed
+ to OptionParser, just like in the 'usage' and 'version' strings.
+ (This is *not* done in the 'description' passed to OptionGroup.)
+
+C API
+-----
+
+- PyImport_ExecCodeModule() and PyImport_ExecCodeModuleEx(): if an
+ error occurs while loading the module, these now delete the module's
+ entry from sys.modules. All ways of loading modules eventually call
+ one of these, so this is an error-case change in semantics for all
+ ways of loading modules. In rare cases, a module loader may wish
+ to keep a module object in sys.modules despite that the module's
+ code cannot be executed. In such cases, the module loader must
+ arrange to reinsert the name and module object in sys.modules.
+ PyImport_ReloadModule() has been changed to reinsert the original
+ module object into sys.modules if the module reload fails, so that
+ its visible semantics have not changed.
+
+- A large pile of datetime field-extraction macros is now documented,
+ thanks to Anthony Tuininga (patch #986010).
+
+Documentation
+-------------
+
+- Improved the tutorial on creating types in C.
+
+ - point out the importance of reassigning data members before
+ assigning their values
+
+ - correct my misconception about return values from visitprocs. Sigh.
+
+ - mention the labor saving Py_VISIT and Py_CLEAR macros.
+
+- Major rewrite of the math module docs, to address common confusions.
+
+Tests
+-----
+
+- The test data files for the decimal test suite are now installed on
+ platforms that use the Makefile.
+
+- SF patch 995225: The test file testtar.tar accidentally contained
+ CVS keywords (like $Id$), which could cause spurious failures in
+ test_tarfile.py depending on how the test file was checked out.
+
+
+What's New in Python 2.4 alpha 1?
+=================================
+
+*Release date: 08-JUL-2004*
+
+Core and builtins
+-----------------
+
+- weakref.ref is now the type object also known as
+ weakref.ReferenceType; it can be subclassed like any other new-style
+ class. There's less per-entry overhead in WeakValueDictionary
+ objects now (one object instead of three).
+
+- Bug #951851: Python crashed when reading import table of certain
+ Windows DLLs.
+
+- Bug #215126. The locals argument to eval(), execfile(), and exec now
+ accept any mapping type.
+
+- marshal now shares interned strings. This change introduces
+ a new .pyc magic.
+
+- Bug #966623. classes created with type() in an exec(, {}) don't
+ have a __module__, but code in typeobject assumed it would always
+ be there.
+
+- Python no longer relies on the LC_NUMERIC locale setting to be
+ the "C" locale; as a result, it no longer tries to prevent changing
+ the LC_NUMERIC category.
+
+- Bug #952807: Unpickling pickled instances of subclasses of
+ datetime.date, datetime.datetime and datetime.time could yield insane
+ objects. Thanks to Jiwon Seo for a fix.
+
+- Bug #845802: Python crashes when __init__.py is a directory.
+
+- Unicode objects received two new methods: iswide() and width().
+ These query East Asian width information, as specified in Unicode
+ TR11.
+
+- Improved the tuple hashing algorithm to give fewer collisions in
+ common cases. Fixes bug #942952.
+
+- Implemented generator expressions (PEP 289). Coded by Jiwon Seo.
+
+- Enabled the profiling of C extension functions (and builtins) - check
+ new documentation and modified profile and bdb modules for more details
+
+- Set file.name to the object passed to open (instead of a new string)
+
+- Moved tracebackobject into traceback.h and renamed to PyTracebackObject
+
+- Optimized the byte coding for multiple assignments like "a,b=b,a" and
+ "a,b,c=1,2,3". Improves their speed by 25% to 30%.
+
+- Limit the nested depth of a tuple for the second argument to isinstance()
+ and issubclass() to the recursion limit of the interpreter.
+ Fixes bug #858016 .
+
+- Optimized dict iterators, creating separate types for each
+ and having them reveal their length. Also optimized the
+ methods: keys(), values(), and items().
+
+- Implemented a newcode opcode, LIST_APPEND, that simplifies
+ the generated bytecode for list comprehensions and further
+ improves their performance (about 35%).
+
+- Implemented rich comparisons for floats, which seems to make
+ comparisons involving NaNs somewhat less surprising when the
+ underlying C compiler actually implements C99 semantics.
+
+- Optimized list.extend() to save memory and no longer create
+ intermediate sequences. Also, extend() now pre-allocates the
+ needed memory whenever the length of the iterable is known in
+ advance -- this halves the time to extend the list.
+
+- Optimized list resize operations to make fewer calls to the system
+ realloc(). Significantly speeds up list appends, list pops,
+ list comprehensions, and the list constructor (when the input iterable
+ length is not known).
+
+- Changed the internal list over-allocation scheme. For larger lists,
+ overallocation ranged between 3% and 25%. Now, it is a constant 12%.
+ For smaller lists (n<8), overallocation was upto eight elements. Now,
+ the overallocation is no more than three elements -- this improves space
+ utilization for applications that have large numbers of small lists.
+
+- Most list bodies now get re-used rather than freed. Speeds up list
+ instantiation and deletion by saving calls to malloc() and free().
+
+- The dict.update() method now accepts all the same argument forms
+ as the dict() constructor. This now includes item lists and/or
+ keyword arguments.
+
+- Support for arbitrary objects supporting the read-only buffer
+ interface as the co_code field of code objects (something that was
+ only possible to create from C code) has been removed.
+
+- Made omitted callback and None equivalent for weakref.ref() and
+ weakref.proxy(); the None case wasn't handled correctly in all
+ cases.
+
+- Fixed problem where PyWeakref_NewRef() and PyWeakref_NewProxy()
+ assumed that initial existing entries in an object's weakref list
+ would not be removed while allocating a new weakref object. Since
+ GC could be invoked at that time, however, that assumption was
+ invalid. In a truly obscure case of GC being triggered during
+ creation for a new weakref object for an referent which already
+ has a weakref without a callback which is only referenced from
+ cyclic trash, a memory error can occur. This consistently created a
+ segfault in a debug build, but provided less predictable behavior in
+ a release build.
+
+- input() builtin function now respects compiler flags such as
+ __future__ statements. SF patch 876178.
+
+- Removed PendingDeprecationWarning from apply(). apply() remains
+ deprecated, but the nuisance warning will not be issued.
+
+- At Python shutdown time (Py_Finalize()), 2.3 called cyclic garbage
+ collection twice, both before and after tearing down modules. The
+ call after tearing down modules has been disabled, because too much
+ of Python has been torn down then for __del__ methods and weakref
+ callbacks to execute sanely. The most common symptom was a sequence
+ of uninformative messages on stderr when Python shut down, produced
+ by threads trying to raise exceptions, but unable to report the nature
+ of their problems because too much of the sys module had already been
+ destroyed.
+
+- Removed FutureWarnings related to hex/oct literals and conversions
+ and left shifts. (Thanks to Kalle Svensson for SF patch 849227.)
+ This addresses most of the remaining semantic changes promised by
+ PEP 237, except for repr() of a long, which still shows the trailing
+ 'L'. The PEP appears to promise warnings for operations that
+ changed semantics compared to Python 2.3, but this is not
+ implemented; we've suffered through enough warnings related to
+ hex/oct literals and I think it's best to be silent now.
+
+- For str and unicode objects, the ljust(), center(), and rjust()
+ methods now accept an optional argument specifying a fill
+ character other than a space.
+
+- When method objects have an attribute that can be satisfied either
+ by the function object or by the method object, the function
+ object's attribute usually wins. Christian Tismer pointed out that
+ that this is really a mistake, because this only happens for special
+ methods (like __reduce__) where the method object's version is
+ really more appropriate than the function's attribute. So from now
+ on, all method attributes will have precedence over function
+ attributes with the same name.
+
+- Critical bugfix, for SF bug 839548: if a weakref with a callback,
+ its callback, and its weakly referenced object, all became part of
+ cyclic garbage during a single run of garbage collection, the order
+ in which they were torn down was unpredictable. It was possible for
+ the callback to see partially-torn-down objects, leading to immediate
+ segfaults, or, if the callback resurrected garbage objects, to
+ resurrect insane objects that caused segfaults (or other surprises)
+ later. In one sense this wasn't surprising, because Python's cyclic gc
+ had no knowledge of Python's weakref objects. It does now. When
+ weakrefs with callbacks become part of cyclic garbage now, those
+ weakrefs are cleared first. The callbacks don't trigger then,
+ preventing the problems. If you need callbacks to trigger, then just
+ as when cyclic gc is not involved, you need to write your code so
+ that weakref objects outlive the objects they weakly reference.
+
+- Critical bugfix, for SF bug 840829: if cyclic garbage collection
+ happened to occur during a weakref callback for a new-style class
+ instance, subtle memory corruption was the result (in a release build;
+ in a debug build, a segfault occurred reliably very soon after).
+ This has been repaired.
+
+- Compiler flags set in PYTHONSTARTUP are now active in __main__.
+
+- Added two builtin types, set() and frozenset().
+
+- Added a reversed() builtin function that returns a reverse iterator
+ over a sequence.
+
+- Added a sorted() builtin function that returns a new sorted list
+ from any iterable.
+
+- CObjects are now mutable (on the C level) through PyCObject_SetVoidPtr.
+
+- list.sort() now supports three keyword arguments: cmp, key, and reverse.
+ The key argument can be a function of one argument that extracts a
+ comparison key from the original record: mylist.sort(key=str.lower).
+ The reverse argument is a boolean value and if True will change the
+ sort order as if the comparison arguments were reversed. In addition,
+ the documentation has been amended to provide a guarantee that all sorts
+ starting with Py2.3 are guaranteed to be stable (the relative order of
+ records with equal keys is unchanged).
+
+- Added test whether wchar_t is signed or not. A signed wchar_t is not
+ usable as internal unicode type base for Py_UNICODE since the
+ unicode implementation assumes an unsigned type.
+
+- Fixed a bug in the cache of length-one Unicode strings that could
+ lead to a seg fault. The specific problem occurred when an earlier,
+ non-fatal error left an uninitialized Unicode object in the
+ freelist.
+
+- The % formatting operator now supports '%F' which is equivalent to
+ '%f'. This has always been documented but never implemented.
+
+- complex(obj) could leak a little memory if obj wasn't a string or
+ number.
+
+- zip() with no arguments now returns an empty list instead of raising
+ a TypeError exception.
+
+- obj.__contains__() now returns True/False instead of 1/0. SF patch
+ 820195.
+
+- Python no longer tries to be smart about recursive comparisons.
+ When comparing containers with cyclic references to themselves it
+ will now just hit the recursion limit. See SF patch 825639.
+
+- str and unicode builtin types now have an rsplit() method that is
+ same as split() except that it scans the string from the end
+ working towards the beginning. See SF feature request 801847.
+
+- Fixed a bug in object.__reduce_ex__ when using protocol 2. Failure
+ to clear the error when attempts to get the __getstate__ attribute
+ fail caused intermittent errors and odd behavior.
+
+- buffer objects based on other objects no longer cache a pointer to
+ the data and the data length. Instead, the appropriate tp_as_buffer
+ method is called as necessary.
+
+- fixed: if a file is opened with an explicit buffer size >= 1, repeated
+ close() calls would attempt to free() the buffer already free()ed on
+ the first call.
+
+
+Extension modules
+-----------------
+
+- Added socket.getservbyport(), and make the second argument in
+ getservbyname() and getservbyport() optional.
+
+- time module code that deals with input POSIX timestamps will now raise
+ ValueError if more than a second is lost in precision when the
+ timestamp is cast to the platform C time_t type. There's no chance
+ that the platform will do anything sensible with the result in such
+ cases. This includes ctime(), localtime() and gmtime(). Assorted
+ fromtimestamp() and utcfromtimestamp() methods in the datetime module
+ were also protected. Closes bugs #919012 and 975996.
+
+- fcntl.ioctl now warns if the mutate flag is not specified.
+
+- nt now properly allows to refer to UNC roots, e.g. in nt.stat().
+
+- the weakref module now supports additional objects: array.array,
+ sre.pattern_objects, file objects, and sockets.
+
+- operator.isMappingType() and operator.isSequenceType() now give
+ fewer false positives.
+
+- socket.sslerror is now a subclass of socket.error . Also added
+ socket.error to the socket module's C API.
+
+- Bug #920575: A problem where the _locale module segfaults on
+ nl_langinfo(ERA) caused by GNU libc's illegal NULL return is fixed.
+
+- array objects now support the copy module. Also, their resizing
+ scheme has been updated to match that used for list objects. This improves
+ the performance (speed and memory usage) of append() operations.
+ Also, array.array() and array.extend() now accept any iterable argument
+ for repeated appends without needing to create another temporary array.
+
+- cStringIO.writelines() now accepts any iterable argument and writes
+ the lines one at a time rather than joining them and writing once.
+ Made a parallel change to StringIO.writelines(). Saves memory and
+ makes suitable for use with generator expressions.
+
+- time.strftime() now checks that the values in its time tuple argument
+ are within the proper boundaries to prevent possible crashes from the
+ platform's C library implementation of strftime(). Can possibly
+ break code that uses values outside the range that didn't cause
+ problems previously (such as sitting day of year to 0). Fixes bug
+ #897625.
+
+- The socket module now supports Bluetooth sockets, if the
+ system has <bluetooth/bluetooth.h>
+
+- Added a collections module containing a new datatype, deque(),
+ offering high-performance, thread-safe, memory friendly appends
+ and pops on either side of the deque.
+
+- Several modules now take advantage of collections.deque() for
+ improved performance: Queue, mutex, shlex, threading, and pydoc.
+
+- The operator module has two new functions, attrgetter() and
+ itemgetter() which are useful for creating fast data extractor
+ functions for map(), list.sort(), itertools.groupby(), and
+ other functions that expect a function argument.
+
+- socket.SHUT_{RD,WR,RDWR} was added.
+
+- os.getsid was added.
+
+- The pwd module incorrectly advertised its struct type as
+ struct_pwent; this has been renamed to struct_passwd. (The old name
+ is still supported for backwards compatibility.)
+
+- The xml.parsers.expat module now provides Expat 1.95.7.
+
+- socket.IPPROTO_IPV6 was added.
+
+- readline.clear_history was added.
+
+- select.select() now accepts sequences for its first three arguments.
+
+- cStringIO now supports the f.closed attribute.
+
+- The signal module now exposes SIGRTMIN and SIGRTMAX (if available).
+
+- curses module now supports use_default_colors(). [patch #739124]
+
+- Bug #811028: ncurses.h breakage on FreeBSD/MacOS X
+
+- Bug #814613: INET_ADDRSTRLEN fix needed for all compilers on SGI
+
+- Implemented non-recursive SRE matching scheme (#757624).
+
+- Implemented (?(id/name)yes|no) support in SRE (#572936).
+
+- random.seed() with no arguments or None uses time.time() as a default
+ seed. Modified to match Py2.2 behavior and use fractional seconds so
+ that successive runs are more likely to produce different sequences.
+
+- random.Random has a new method, getrandbits(k), which returns an int
+ with k random bits. This method is now an optional part of the API
+ for user defined generators. Any generator that defines genrandbits()
+ can now use randrange() for ranges with a length >= 2**53. Formerly,
+ randrange would return only even numbers for ranges that large (see
+ SF bug #812202). Generators that do not define genrandbits() now
+ issue a warning when randrange() is called with a range that large.
+
+- itertools has a new function, groupby() for aggregating iterables
+ into groups sharing the same key (as determined by a key function).
+ It offers some of functionality of SQL's groupby keyword and of
+ the Unix uniq filter.
+
+- itertools now has a new tee() function which produces two independent
+ iterators from a single iterable.
+
+- itertools.izip() with no arguments now returns an empty iterator instead
+ of raising a TypeError exception.
+
+- Fixed #853061: allow BZ2Compressor.compress() to receive an empty string
+ as parameter.
+
+Library
+-------
+
+- Added a new module: cProfile, a C profiler with the same interface as the
+ profile module. cProfile avoids some of the drawbacks of the hotshot
+ profiler and provides a bit more information than the other two profilers.
+ Based on "lsprof" (patch #1212837).
+
+- Bug #1266283: The new function "lexists" is now in os.path.__all__.
+
+- Bug #981530: Fix UnboundLocalError in shutil.rmtree(). This affects
+ the documented behavior: the function passed to the onerror()
+ handler can now also be os.listdir.
+
+- Bug #754449: threading.Thread objects no longer mask exceptions raised during
+ interpreter shutdown with another exception from attempting to handle the
+ original exception.
+
+- Added decimal.py per PEP 327.
+
+- Bug #981299: rsync is now a recognized protocol in urlparse that uses a
+ "netloc" portion of a URL.
+
+- Bug #919012: shutil.move() will not try to move a directory into itself.
+ Thanks Johannes Gijsbers.
+
+- Bug #934282: pydoc.stripid() is now case-insensitive. Thanks Robin Becker.
+
+- Bug #823209: cmath.log() now takes an optional base argument so that its
+ API matches math.log().
+
+- Bug #957381: distutils bdist_rpm no longer fails on recent RPM versions
+ that generate a -debuginfo.rpm
+
+- os.path.devnull has been added for all supported platforms.
+
+- Fixed #877165: distutils now picks the right C++ compiler command
+ on cygwin and mingw32.
+
+- urllib.urlopen().readline() now handles HTTP/0.9 correctly.
+
+- refactored site.py into functions. Also wrote regression tests for the
+ module.
+
+- The distutils install command now supports the --home option and
+ installation scheme for all platforms.
+
+- asyncore.loop now has a repeat count parameter that defaults to
+ looping forever.
+
+- The distutils sdist command now ignores all .svn directories, in
+ addition to CVS and RCS directories. .svn directories hold
+ administrative files for the Subversion source control system.
+
+- Added a new module: cookielib. Automatic cookie handling for HTTP
+ clients. Also, support for cookielib has been added to urllib2, so
+ urllib2.urlopen() can transparently handle cookies.
+
+- stringprep.py now uses built-in set() instead of sets.Set().
+
+- Bug #876278: Unbounded recursion in modulefinder
+
+- Bug #780300: Swap public and system ID in LexicalHandler.startDTD.
+ Applications relying on the wrong order need to be corrected.
+
+- Bug #926075: Fixed a bug that returns a wrong pattern object
+ for a string or unicode object in sre.compile() when a different
+ type pattern with the same value exists.
+
+- Added countcallers arg to trace.Trace class (--trackcalls command line arg
+ when run from the command prompt).
+
+- Fixed a caching bug in platform.platform() where the argument of 'terse' was
+ not taken into consideration when caching value.
+
+- Added two new command-line arguments for profile (output file and
+ default sort).
+
+- Added global runctx function to profile module
+
+- Add hlist missing entryconfigure and entrycget methods.
+
+- The ptcp154 codec was added for Kazakh character set support.
+
+- Support non-anonymous ftp URLs in urllib2.
+
+- The encodings package will now apply codec name aliases
+ first before starting to try the import of the codec module.
+ This simplifies overriding built-in codecs with external
+ packages, e.g. the included CJK codecs with the JapaneseCodecs
+ package, by adjusting the aliases dictionary in encodings.aliases
+ accordingly.
+
+- base64 now supports RFC 3548 Base16, Base32, and Base64 encoding and
+ decoding standards.
+
+- urllib2 now supports processors. A processor is a handler that
+ implements an xxx_request or xxx_response method. These methods are
+ called for all requests.
+
+- distutils compilers now compile source files in the same order as
+ they are passed to the compiler.
+
+- pprint.pprint() and pprint.pformat() now have additional parameters
+ indent, width and depth.
+
+- Patch #750542: pprint now will pretty print subclasses of list, tuple
+ and dict too, as long as they don't overwrite __repr__().
+
+- Bug #848614: distutils' msvccompiler fails to find the MSVC6
+ compiler because of incomplete registry entries.
+
+- httplib.HTTP.putrequest now offers to omit the implicit Accept-Encoding.
+
+- Patch #841977: modulefinder didn't find extension modules in packages
+
+- imaplib.IMAP4.thread was added.
+
+- Plugged a minor hole in tempfile.mktemp() due to the use of
+ os.path.exists(), switched to using os.lstat() directly if possible.
+
+- bisect.py and heapq.py now have underlying C implementations
+ for better performance.
+
+- heapq.py has two new functions, nsmallest() and nlargest().
+
+- traceback.format_exc has been added (similar to print_exc but it returns
+ a string).
+
+- xmlrpclib.MultiCall has been added.
+
+- poplib.POP3_SSL has been added.
+
+- tmpfile.mkstemp now returns an absolute path even if dir is relative.
+
+- urlparse is RFC 2396 compliant.
+
+- The fieldnames argument to the csv module's DictReader constructor is now
+ optional. If omitted, the first row of the file will be used as the
+ list of fieldnames.
+
+- encodings.bz2_codec was added for access to bz2 compression
+ using "a long string".encode('bz2')
+
+- Various improvements to unittest.py, realigned with PyUnit CVS.
+
+- dircache now passes exceptions to the caller, instead of returning
+ empty lists.
+
+- The bsddb module and dbhash module now support the iterator and
+ mapping protocols which make them more substitutable for dictionaries
+ and shelves.
+
+- The csv module's DictReader and DictWriter classes now accept keyword
+ arguments. This was an omission in the initial implementation.
+
+- The email package handles some RFC 2231 parameters with missing
+ CHARSET fields better. It also includes a patch to parameter
+ parsing when semicolons appear inside quotes.
+
+- sets.py now runs under Py2.2. In addition, the argument restrictions
+ for most set methods (but not the operators) have been relaxed to
+ allow any iterable.
+
+- _strptime.py now has a behind-the-scenes caching mechanism for the most
+ recent TimeRE instance used along with the last five unique directive
+ patterns. The overall module was also made more thread-safe.
+
+- random.cunifvariate() and random.stdgamma() were deprecated in Py2.3
+ and removed in Py2.4.
+
+- Bug #823328: urllib2.py's HTTP Digest Auth support works again.
+
+- Patch #873597: CJK codecs are imported into rank of default codecs.
+
+Tools/Demos
+-----------
+
+- A hotshotmain script was added to the Tools/scripts directory that
+ makes it easy to run a script under control of the hotshot profiler.
+
+- The db2pickle and pickle2db scripts can now dump/load gdbm files.
+
+- The file order on the command line of the pickle2db script was reversed.
+ It is now [ picklefile ] dbfile. This provides better symmetry with
+ db2pickle. The file arguments to both scripts are now source followed by
+ destination in situations where both files are given.
+
+- The pydoc script will display a link to the module documentation for
+ modules determined to be part of the core distribution. The documentation
+ base directory defaults to http://www.python.org/doc/current/lib/ but can
+ be changed by setting the PYTHONDOCS environment variable.
+
+- texcheck.py now detects double word errors.
+
+- md5sum.py mistakenly opened input files in text mode by default, a
+ silent and dangerous change from previous releases. It once again
+ opens input files in binary mode by default. The -t and -b flags
+ remain for compatibility with the 2.3 release, but -b is the default
+ now.
+
+- py-electric-colon now works when pending-delete/delete-selection mode is
+ in effect
+
+- py-help-at-point is no longer bound to the F1 key - it's still bound to
+ C-c C-h
+
+- Pynche was fixed to not crash when there is no ~/.pynche file and no
+ -d option was given.
+
+Build
+-----
+
+- Bug #978645: Modules/getpath.c now builds properly in --disable-framework
+ build under OS X.
+
+- Profiling using gprof is now available if Python is configured with
+ --enable-profiling.
+
+- Profiling the VM using the Pentium TSC is now possible if Python
+ is configured --with-tsc.
+
+- In order to find libraries, setup.py now also looks in /lib64, for use
+ on AMD64.
+
+- Bug #934635: Fixed a bug where the configure script couldn't detect
+ getaddrinfo() properly if the KAME stack had SCTP support.
+
+- Support for missing ANSI C header files (limits.h, stddef.h, etc) was
+ removed.
+
+- Systems requiring the D4, D6 or D7 variants of pthreads are no longer
+ supported (see PEP 11).
+
+- Universal newline support can no longer be disabled (see PEP 11).
+
+- Support for DGUX, SunOS 4, IRIX 4 and Minix was removed (see PEP 11).
+
+- Support for systems requiring --with-dl-dld or --with-sgi-dl was removed
+ (see PEP 11).
+
+- Tests for sizeof(char) were removed since ANSI C mandates that
+ sizeof(char) must be 1.
+
+C API
+-----
+
+- Thanks to Anthony Tuininga, the datetime module now supplies a C API
+ containing type-check macros and constructors. See new docs in the
+ Python/C API Reference Manual for details.
+
+- Private function _PyTime_DoubleToTimet added, to convert a Python
+ timestamp (C double) to platform time_t with some out-of-bounds
+ checking. Declared in new header file timefuncs.h. It would be
+ good to expose some other internal timemodule.c functions there.
+
+- New public functions PyEval_EvaluateFrame and PyGen_New to expose
+ generator objects.
+
+- New public functions Py_IncRef() and Py_DecRef(), exposing the
+ functionality of the Py_XINCREF() and Py_XDECREF macros. Useful for
+ runtime dynamic embedding of Python. See patch #938302, by Bob
+ Ippolito.
+
+- Added a new macro, PySequence_Fast_ITEMS, which retrieves a fast sequence's
+ underlying array of PyObject pointers. Useful for high speed looping.
+
+- Created a new method flag, METH_COEXIST, which causes a method to be loaded
+ even if already defined by a slot wrapper. This allows a __contains__
+ method, for example, to co-exist with a defined sq_contains slot. This
+ is helpful because the PyCFunction can take advantage of optimized calls
+ whenever METH_O or METH_NOARGS flags are defined.
+
+- Added a new function, PyDict_Contains(d, k) which is like
+ PySequence_Contains() but is specific to dictionaries and executes
+ about 10% faster.
+
+- Added three new macros: Py_RETURN_NONE, Py_RETURN_TRUE, and Py_RETURN_FALSE.
+ Each return the singleton they mention after Py_INCREF()ing them.
+
+- Added a new function, PyTuple_Pack(n, ...) for constructing tuples from a
+ variable length argument list of Python objects without having to invoke
+ the more complex machinery of Py_BuildValue(). PyTuple_Pack(3, a, b, c)
+ is equivalent to Py_BuildValue("(OOO)", a, b, c).
+
+Windows
+-------
+
+- The _winreg module could segfault when reading very large registry
+ values, due to unchecked alloca() calls (SF bug 851056). The fix is
+ uses either PyMem_Malloc(n) or PyString_FromStringAndSize(NULL, n),
+ as appropriate, followed by a size check.
+
+- file.truncate() could misbehave if the file was open for update
+ (modes r+, rb+, w+, wb+), and the most recent file operation before
+ the truncate() call was an input operation. SF bug 801631.
+
+
+What's New in Python 2.3 final?
+===============================
+
+*Release date: 29-Jul-2003*
+
+IDLE
+----
+
+- Bug 778400: IDLE hangs when selecting "Edit with IDLE" from explorer.
+ This was unique to Windows, and was fixed by adding an -n switch to
+ the command the Windows installer creates to execute "Edit with IDLE"
+ context-menu actions.
+
+- IDLE displays a new message upon startup: some "personal firewall"
+ kinds of programs (for example, ZoneAlarm) open a dialog of their
+ own when any program opens a socket. IDLE does use sockets, talking
+ on the computer's internal loopback interface. This connection is not
+ visible on any external interface and no data is sent to or received
+ from the Internet. So, if you get such a dialog when opening IDLE,
+ asking whether to let pythonw.exe talk to address 127.0.0.1, say yes,
+ and rest assured no communication external to your machine is taking
+ place. If you don't allow it, IDLE won't be able to start.
+
+
+What's New in Python 2.3 release candidate 2?
+=============================================
+
+*Release date: 24-Jul-2003*
+
+Core and builtins
+-----------------
+
+- It is now possible to import from zipfiles containing additional
+ data bytes before the zip compatible archive. Zipfiles containing a
+ comment at the end are still unsupported.
+
+Extension modules
+-----------------
+
+- A longstanding bug in the parser module's initialization could cause
+ fatal internal refcount confusion when the module got initialized more
+ than once. This has been fixed.
+
+- Fixed memory leak in pyexpat; using the parser's ParseFile() method
+ with open files that aren't instances of the standard file type
+ caused an instance of the bound .read() method to be leaked on every
+ call.
+
+- Fixed some leaks in the locale module.
+
+Library
+-------
+
+- Lib/encodings/rot_13.py when used as a script, now more properly
+ uses the first Python interpreter on your path.
+
+- Removed caching of TimeRE (and thus LocaleTime) in _strptime.py to
+ fix a locale related bug in the test suite. Although another patch
+ was needed to actually fix the problem, the cache code was not
+ restored.
+
+IDLE
+----
+
+- Calltips patches.
+
+Build
+-----
+
+- For MacOSX, added -mno-fused-madd to BASECFLAGS to fix test_coercion
+ on Panther (OSX 10.3).
+
+C API
+-----
+
+Windows
+-------
+
+- The tempfile module could do insane imports on Windows if PYTHONCASEOK
+ was set, making temp file creation impossible. Repaired.
+
+- Add a patch to workaround pthread_sigmask() bugs in Cygwin.
+
+Mac
+---
+
+- Various fixes to pimp.
+
+- Scripts runs with pythonw no longer had full window manager access.
+
+- Don't force boot-disk-only install, for reasons unknown it causes
+ more problems than it solves.
+
+
+What's New in Python 2.3 release candidate 1?
+=============================================
+
+*Release date: 18-Jul-2003*
+
+Core and builtins
+-----------------
+
+- The new function sys.getcheckinterval() returns the last value set
+ by sys.setcheckinterval().
+
+- Several bugs in the symbol table phase of the compiler have been
+ fixed. Errors could be lost and compilation could fail without
+ reporting an error. SF patch 763201.
+
+- The interpreter is now more robust about importing the warnings
+ module. In an executable generated by freeze or similar programs,
+ earlier versions of 2.3 would fail if the warnings module could
+ not be found on the file system. Fixes SF bug 771097.
+
+- A warning about assignments to module attributes that shadow
+ builtins, present in earlier releases of 2.3, has been removed.
+
+- It is not possible to create subclasses of builtin types like str
+ and tuple that define an itemsize. Earlier releases of Python 2.3
+ allowed this by mistake, leading to crashes and other problems.
+
+- The thread_id is now initialized to 0 in a non-thread build. SF bug
+ 770247.
+
+- SF bug 762891: "del p[key]" on proxy object no longer raises SystemError.
+
+Extension modules
+-----------------
+
+- weakref.proxy() can now handle "del obj[i]" for proxy objects
+ defining __delitem__. Formerly, it generated a SystemError.
+
+- SSL no longer crashes the interpreter when the remote side disconnects.
+
+- On Unix the mmap module can again be used to map device files.
+
+- time.strptime now exclusively uses the Python implementation
+ contained within the _strptime module.
+
+- The print slot of weakref proxy objects was removed, because it was
+ not consistent with the object's repr slot.
+
+- The mmap module only checks file size for regular files, not
+ character or block devices. SF patch 708374.
+
+- The cPickle Pickler garbage collection support was fixed to traverse
+ the find_class attribute, if present.
+
+- There are several fixes for the bsddb3 wrapper module.
+
+ bsddb3 no longer crashes if an environment is closed before a cursor
+ (SF bug 763298).
+
+ The DB and DBEnv set_get_returns_none function was extended to take
+ a level instead of a boolean flag. The new level 2 means that in
+ addition, cursor.set()/.get() methods return None instead of raising
+ an exception.
+
+ A typo was fixed in DBCursor.join_item(), preventing a crash.
+
+Library
+-------
+
+- distutils now supports MSVC 7.1
+
+- doctest now examines all docstrings by default. Previously, it would
+ skip over functions with private names (as indicated by the underscore
+ naming convention). The old default created too much of a risk that
+ user tests were being skipped inadvertently. Note, this change could
+ break code in the unlikely case that someone had intentionally put
+ failing tests in the docstrings of private functions. The breakage
+ is easily fixable by specifying the old behavior when calling testmod()
+ or Tester().
+
+- There were several fixes to the way dumbdbms are closed. It's vital
+ that a dumbdbm database be closed properly, else the on-disk data
+ and directory files can be left in mutually inconsistent states.
+ dumbdbm.py's _Database.__del__() method attempted to close the
+ database properly, but a shutdown race in _Database._commit() could
+ prevent this from working, so that a program trusting __del__() to
+ get the on-disk files in synch could be badly surprised. The race
+ has been repaired. A sync() method was also added so that shelve
+ can guarantee data is written to disk.
+
+ The close() method can now be called more than once without complaint.
+
+- The classes in threading.py are now new-style classes. That they
+ weren't before was an oversight.
+
+- The urllib2 digest authentication handlers now define the correct
+ auth_header. The earlier versions would fail at runtime.
+
+- SF bug 763023: fix uncaught ZeroDivisionError in difflib ratio methods
+ when there are no lines.
+
+- SF bug 763637: fix exception in Tkinter with after_cancel
+ which could occur with Tk 8.4
+
+- SF bug 770601: CGIHTTPServer.py now passes the entire environment
+ to child processes.
+
+- SF bug 765238: add filter to fnmatch's __all__.
+
+- SF bug 748201: make time.strptime() error messages more helpful.
+
+- SF patch 764470: Do not dump the args attribute of a Fault object in
+ xmlrpclib.
+
+- SF patch 549151: urllib and urllib2 now redirect POSTs on 301
+ responses.
+
+- SF patch 766650: The whichdb module was fixed to recognize dbm files
+ generated by gdbm on OS/2 EMX.
+
+- SF bugs 763047 and 763052: fixes bug of timezone value being left as
+ -1 when ``time.tzname[0] == time.tzname[1] and not time.daylight``
+ is true when it should only when time.daylight is true.
+
+- SF bug 764548: re now allows subclasses of str and unicode to be
+ used as patterns.
+
+- SF bug 763637: In Tkinter, change after_cancel() to handle tuples
+ of varying sizes. Tk 8.4 returns a different number of values
+ than Tk 8.3.
+
+- SF bug 763023: difflib.ratio() did not catch zero division.
+
+- The Queue module now has an __all__ attribute.
+
+Tools/Demos
+-----------
+
+- See Lib/idlelib/NEWS.txt for IDLE news.
+
+- SF bug 753592: webchecker/wsgui now handles user supplied directories.
+
+- The trace.py script has been removed. It is now in the standard library.
+
+Build
+-----
+
+- Python now compiles with -fno-strict-aliasing if possible (SF bug 766696).
+
+- The socket module compiles on IRIX 6.5.10.
+
+- An irix64 system is treated the same way as an irix6 system (SF
+ patch 764560).
+
+- Several definitions were missing on FreeBSD 5.x unless the
+ __BSD_VISIBLE symbol was defined. configure now defines it as
+ needed.
+
+C API
+-----
+
+- Unicode objects now support mbcs as a built-in encoding, so the C
+ API can use it without deferring to the encodings package.
+
+Windows
+-------
+
+- The Windows implementation of PyThread_start_new_thread() never
+ checked error returns from Windows functions correctly. As a result,
+ it could claim to start a new thread even when the Microsoft
+ _beginthread() function failed (due to "too many threads" -- this is
+ on the order of thousands when it happens). In these cases, the
+ Python exception ::
+
+ thread.error: can't start new thread
+
+ is raised now.
+
+- SF bug 766669: Prevent a GPF on interpreter exit when sockets are in
+ use. The interpreter now calls WSACleanup() from Py_Finalize()
+ instead of from DLL teardown.
+
+Mac
+---
+
+- Bundlebuilder now inherits default values in the right way. It was
+ previously possible for app bundles to get a type of "BNDL" instead
+ of "APPL." Other improvements include, a --build-id option to
+ specify the CFBundleIdentifier and using the --python option to set
+ the executable in the bundle.
+
+- Fixed two bugs in MacOSX framework handling.
+
+- pythonw did not allow user interaction in 2.3rc1, this has been fixed.
+
+- Python is now compiled with -mno-fused-madd, making all tests pass
+ on Panther.
+
+What's New in Python 2.3 beta 2?
+================================
+
+*Release date: 29-Jun-2003*
+
+Core and builtins
+-----------------
+
+- A program can now set the environment variable PYTHONINSPECT to some
+ string value in Python, and cause the interpreter to enter the
+ interactive prompt at program exit, as if Python had been invoked
+ with the -i option.
+
+- list.index() now accepts optional start and stop arguments. Similar
+ changes were made to UserList.index(). SF feature request 754014.
+
+- SF patch 751998 fixes an unwanted side effect of the previous fix
+ for SF bug 742860 (the next item).
+
+- SF bug 742860: "WeakKeyDictionary __delitem__ uses iterkeys". This
+ wasn't threadsafe, was very inefficient (expected time O(len(dict))
+ instead of O(1)), and could raise a spurious RuntimeError if another
+ thread mutated the dict during __delitem__, or if a comparison function
+ mutated it. It also neglected to raise KeyError when the key wasn't
+ present; didn't raise TypeError when the key wasn't of a weakly
+ referencable type; and broke various more-or-less obscure dict
+ invariants by using a sequence of equality comparisons over the whole
+ set of dict keys instead of computing the key's hash code to narrow
+ the search to those keys with the same hash code. All of these are
+ considered to be bugs. A new implementation of __delitem__ repairs all
+ that, but note that fixing these bugs may change visible behavior in
+ code relying (whether intentionally or accidentally) on old behavior.
+
+- SF bug 734869: Fixed a compiler bug that caused a fatal error when
+ compiling a list comprehension that contained another list comprehension
+ embedded in a lambda expression.
+
+- SF bug 705231: builtin pow() no longer lets the platform C pow()
+ raise -1.0 to integer powers, because (at least) glibc gets it wrong
+ in some cases. The result should be -1.0 if the power is odd and 1.0
+ if the power is even, and any float with a sufficiently large exponent
+ is (mathematically) an exact even integer.
+
+- SF bug 759227: A new-style class that implements __nonzero__() must
+ return a bool or int (but not an int subclass) from that method. This
+ matches the restriction on classic classes.
+
+- The encoding attribute has been added for file objects, and set to
+ the terminal encoding on Unix and Windows.
+
+- The softspace attribute of file objects became read-only by oversight.
+ It's writable again.
+
+- Reverted a 2.3 beta 1 change to iterators for subclasses of list and
+ tuple. By default, the iterators now access data elements directly
+ instead of going through __getitem__. If __getitem__ access is
+ preferred, then __iter__ can be overridden.
+
+- SF bug 735247: The staticmethod and super types participate in
+ garbage collection. Before this change, it was possible for leaks to
+ occur in functions with non-global free variables that used these types.
+
+Extension modules
+-----------------
+
+- the socket module has a new exception, socket.timeout, to allow
+ timeouts to be handled separately from other socket errors.
+
+- SF bug 751276: cPickle has fixed to propagate exceptions raised in
+ user code. In earlier versions, cPickle caught and ignored any
+ exception when it performed operations that it expected to raise
+ specific exceptions like AttributeError.
+
+- cPickle Pickler and Unpickler objects now participate in garbage
+ collection.
+
+- mimetools.choose_boundary() could return duplicate strings at times,
+ especially likely on Windows. The strings returned are now guaranteed
+ unique within a single program run.
+
+- thread.interrupt_main() raises KeyboardInterrupt in the main thread.
+ dummy_thread has also been modified to try to simulate the behavior.
+
+- array.array.insert() now treats negative indices as being relative
+ to the end of the array, just like list.insert() does. (SF bug #739313)
+
+- The datetime module classes datetime, time, and timedelta are now
+ properly subclassable.
+
+- _tkinter.{get|set}busywaitinterval was added.
+
+- itertools.islice() now accepts stop=None as documented.
+ Fixes SF bug #730685.
+
+- the bsddb185 module is built in one restricted instance -
+ /usr/include/db.h exists and defines HASHVERSION to be 2. This is true
+ for many BSD-derived systems.
+
+
+Library
+-------
+
+- Some happy doctest extensions from Jim Fulton have been added to
+ doctest.py. These are already being used in Zope3. The two
+ primary ones:
+
+ doctest.debug(module, name) extracts the doctests from the named object
+ in the given module, puts them in a temp file, and starts pdb running
+ on that file. This is great when a doctest fails.
+
+ doctest.DocTestSuite(module=None) returns a synthesized unittest
+ TestSuite instance, to be run by the unittest framework, which
+ runs all the doctests in the module. This allows writing tests in
+ doctest style (which can be clearer and shorter than writing tests
+ in unittest style), without losing unittest's powerful testing
+ framework features (which doctest lacks).
+
+- For compatibility with doctests created before 2.3, if an expected
+ output block consists solely of "1" and the actual output block
+ consists solely of "True", it's accepted as a match; similarly
+ for "0" and "False". This is quite un-doctest-like, but is practical.
+ The behavior can be disabled by passing the new doctest module
+ constant DONT_ACCEPT_TRUE_FOR_1 to the new optionflags optional
+ argument.
+
+- ZipFile.testzip() now only traps BadZipfile exceptions. Previously,
+ a bare except caught to much and reported all errors as a problem
+ in the archive.
+
+- The logging module now has a new function, makeLogRecord() making
+ LogHandler easier to interact with DatagramHandler and SocketHandler.
+
+- The cgitb module has been extended to support plain text display (SF patch
+ 569574).
+
+- A brand new version of IDLE (from the IDLEfork project at
+ SourceForge) is now included as Lib/idlelib. The old Tools/idle is
+ no more.
+
+- Added a new module: trace (documentation missing). This module used
+ to be distributed in Tools/scripts. It uses sys.settrace() to trace
+ code execution -- either function calls or individual lines. It can
+ generate tracing output during execution or a post-mortem report of
+ code coverage.
+
+- The threading module has new functions settrace() and setprofile()
+ that cooperate with the functions of the same name in the sys
+ module. A function registered with the threading module will
+ be used for all threads it creates. The new trace module uses this
+ to provide tracing for code running in threads.
+
+- copy.py: applied SF patch 707900, fixing bug 702858, by Steven
+ Taschuk. Copying a new-style class that had a reference to itself
+ didn't work. (The same thing worked fine for old-style classes.)
+ Builtin functions are now treated as atomic, fixing bug #746304.
+
+- difflib.py has two new functions: context_diff() and unified_diff().
+
+- More fixes to urllib (SF 549151): (a) When redirecting, always use
+ GET. This is common practice and more-or-less sanctioned by the
+ HTTP standard. (b) Add a handler for 307 redirection, which becomes
+ an error for POST, but a regular redirect for GET and HEAD
+
+- Added optional 'onerror' argument to os.walk(), to control error
+ handling.
+
+- inspect.is{method|data}descriptor was added, to allow pydoc display
+ __doc__ of data descriptors.
+
+- Fixed socket speed loss caused by use of the _socketobject wrapper class
+ in socket.py.
+
+- timeit.py now checks the current directory for imports.
+
+- urllib2.py now knows how to order proxy classes, so the user doesn't
+ have to insert it in front of other classes, nor do dirty tricks like
+ inserting a "dummy" HTTPHandler after a ProxyHandler when building an
+ opener with proxy support.
+
+- Iterators have been added for dbm keys.
+
+- random.Random objects can now be pickled.
+
+Tools/Demos
+-----------
+
+- pydoc now offers help on keywords and topics.
+
+- Tools/idle is gone; long live Lib/idlelib.
+
+- diff.py prints file diffs in context, unified, or ndiff formats,
+ providing a command line interface to difflib.py.
+
+- texcheck.py is a new script for making a rough validation of Python LaTeX
+ files.
+
+Build
+-----
+
+- Setting DESTDIR during 'make install' now allows specifying a
+ different root directory.
+
+C API
+-----
+
+- PyType_Ready(): If a type declares that it participates in gc
+ (Py_TPFLAGS_HAVE_GC), and its base class does not, and its base class's
+ tp_free slot is the default _PyObject_Del, and type does not define
+ a tp_free slot itself, _PyObject_GC_Del is assigned to type->tp_free.
+ Previously _PyObject_Del was inherited, which could at best lead to a
+ segfault. In addition, if even after this magic the type's tp_free
+ slot is _PyObject_Del or NULL, and the type is a base type
+ (Py_TPFLAGS_BASETYPE), TypeError is raised: since the type is a base
+ type, its dealloc function must call type->tp_free, and since the type
+ is gc'able, tp_free must not be NULL or _PyObject_Del.
+
+- PyThreadState_SetAsyncExc(): A new API (deliberately accessible only
+ from C) to interrupt a thread by sending it an exception. It is
+ intentional that you have to write your own C extension to call it
+ from Python.
+
+
+New platforms
+-------------
+
+None this time.
+
+Tests
+-----
+
+- test_imp rewritten so that it doesn't raise RuntimeError if run as a
+ side effect of being imported ("import test.autotest").
+
+Windows
+-------
+
+- The Windows installer ships with Tcl/Tk 8.4.3 (upgraded from 8.4.1).
+
+- The installer always suggested that Python be installed on the C:
+ drive, due to a hardcoded "C:" generated by the Wise installation
+ wizard. People with machines where C: is not the system drive
+ usually want Python installed on whichever drive is their system drive
+ instead. We removed the hardcoded "C:", and two testers on machines
+ where C: is not the system drive report that the installer now
+ suggests their system drive. Note that you can always select the
+ directory you want in the "Select Destination Directory" dialog --
+ that's what it's for.
+
+Mac
+---
+
+- There's a new module called "autoGIL", which offers a mechanism to
+ automatically release the Global Interpreter Lock when an event loop
+ goes to sleep, allowing other threads to run. It's currently only
+ supported on OSX, in the Mach-O version.
+- The OSA modules now allow direct access to properties of the
+ toplevel application class (in AppleScript terminology).
+- The Package Manager can now update itself.
+
+SourceForge Bugs and Patches Applied
+------------------------------------
+
+430160, 471893, 501716, 542562, 549151, 569574, 595837, 596434,
+598163, 604210, 604716, 610332, 612627, 614770, 620190, 621891,
+622042, 639139, 640236, 644345, 649742, 649742, 658233, 660022,
+661318, 661676, 662807, 662923, 666219, 672855, 678325, 682347,
+683486, 684981, 685773, 686254, 692776, 692959, 693094, 696777,
+697989, 700827, 703666, 708495, 708604, 708901, 710733, 711902,
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+724588, 724767, 724767, 725942, 726150, 726446, 726869, 727051,
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+732143, 732234, 732284, 732284, 732479, 732761, 732783, 732951,
+733667, 733781, 734118, 734231, 734869, 735051, 735293, 735527,
+735613, 735694, 736962, 736962, 737970, 738066, 739313, 740055,
+740234, 740301, 741806, 742126, 742741, 742860, 742860, 742911,
+744041, 744104, 744238, 744687, 744877, 745055, 745478, 745525,
+745620, 746012, 746304, 746366, 746801, 746953, 747348, 747667,
+747954, 748846, 748849, 748973, 748975, 749191, 749210, 749759,
+749831, 749911, 750008, 750092, 750542, 750595, 751038, 751107,
+751276, 751451, 751916, 751941, 751956, 751998, 752671, 753451,
+753602, 753617, 753845, 753925, 754014, 754340, 754447, 755031,
+755087, 755147, 755245, 755683, 755987, 756032, 756996, 757058,
+757229, 757818, 757821, 757822, 758112, 758910, 759227, 759889,
+760257, 760703, 760792, 761104, 761337, 761519, 761830, 762455
+
+
+What's New in Python 2.3 beta 1?
+================================
+
+*Release date: 25-Apr-2003*
+
+Core and builtins
+-----------------
+
+- New format codes B, H, I, k and K have been implemented for
+ PyArg_ParseTuple and PyBuild_Value.
+
+- New builtin function sum(seq, start=0) returns the sum of all the
+ items in iterable object seq, plus start (items are normally numbers,
+ and cannot be strings).
+
+- bool() called without arguments now returns False rather than
+ raising an exception. This is consistent with calling the
+ constructors for the other builtin types -- called without argument
+ they all return the false value of that type. (SF patch #724135)
+
+- In support of PEP 269 (making the pgen parser generator accessible
+ from Python), some changes to the pgen code structure were made; a
+ few files that used to be linked only with pgen are now linked with
+ Python itself.
+
+- The repr() of a weakref object now shows the __name__ attribute of
+ the referenced object, if it has one.
+
+- super() no longer ignores data descriptors, except __class__. See
+ the thread started at
+ http://mail.python.org/pipermail/python-dev/2003-April/034338.html
+
+- list.insert(i, x) now interprets negative i as it would be
+ interpreted by slicing, so negative values count from the end of the
+ list. This was the only place where such an interpretation was not
+ placed on a list index.
+
+- range() now works even if the arguments are longs with magnitude
+ larger than sys.maxint, as long as the total length of the sequence
+ fits. E.g., range(2**100, 2**101, 2**100) is the following list:
+ [1267650600228229401496703205376L]. (SF patch #707427.)
+
+- Some horridly obscure problems were fixed involving interaction
+ between garbage collection and old-style classes with "ambitious"
+ getattr hooks. If an old-style instance didn't have a __del__ method,
+ but did have a __getattr__ hook, and the instance became reachable
+ only from an unreachable cycle, and the hook resurrected or deleted
+ unreachable objects when asked to resolve "__del__", anything up to
+ a segfault could happen. That's been repaired.
+
+- dict.pop now takes an optional argument specifying a default
+ value to return if the key is not in the dict. If a default is not
+ given and the key is not found, a KeyError will still be raised.
+ Parallel changes were made to UserDict.UserDict and UserDict.DictMixin.
+ [SF patch #693753] (contributed by Michael Stone.)
+
+- sys.getfilesystemencoding() was added to expose
+ Py_FileSystemDefaultEncoding.
+
+- New function sys.exc_clear() clears the current exception. This is
+ rarely needed, but can sometimes be useful to release objects
+ referenced by the traceback held in sys.exc_info()[2]. (SF patch
+ #693195.)
+
+- On 64-bit systems, a dictionary could contain duplicate long/int keys
+ if the key value was larger than 2**32. See SF bug #689659.
+
+- Fixed SF bug #663074. The codec system was using global static
+ variables to store internal data. As a result, any attempts to use the
+ unicode system with multiple active interpreters, or successive
+ interpreter executions, would fail.
+
+- "%c" % u"a" now returns a unicode string instead of raising a
+ TypeError. u"%c" % 0xffffffff now raises a OverflowError instead
+ of a ValueError to be consistent with "%c" % 256. See SF patch #710127.
+
+Extension modules
+-----------------
+
+- The socket module now provides the functions inet_pton and inet_ntop
+ for converting between string and packed representation of IP
+ addresses. There is also a new module variable, has_ipv6, which is
+ True iff the current Python has IPv6 support. See SF patch #658327.
+
+- Tkinter wrappers around Tcl variables now pass objects directly
+ to Tcl, instead of first converting them to strings.
+
+- The .*? pattern in the re module is now special-cased to avoid the
+ recursion limit. (SF patch #720991 -- many thanks to Gary Herron
+ and Greg Chapman.)
+
+- New function sys.call_tracing() allows pdb to debug code
+ recursively.
+
+- New function gc.get_referents(obj) returns a list of objects
+ directly referenced by obj. In effect, it exposes what the object's
+ tp_traverse slot does, and can be helpful when debugging memory
+ leaks.
+
+- The iconv module has been removed from this release.
+
+- The platform-independent routines for packing floats in IEEE formats
+ (struct.pack's <f, >f, <d, and >d codes; pickle and cPickle's protocol 1
+ pickling of floats) ignored that rounding can cause a carry to
+ propagate. The worst consequence was that, in rare cases, <f and >f
+ could produce strings that, when unpacked again, were a factor of 2
+ away from the original float. This has been fixed. See SF bug
+ #705836.
+
+- New function time.tzset() provides access to the C library tzset()
+ function, if supported. (SF patch #675422.)
+
+- Using createfilehandler, deletefilehandler, createtimerhandler functions
+ on Tkinter.tkinter (_tkinter module) no longer crashes the interpreter.
+ See SF bug #692416.
+
+- Modified the fcntl.ioctl() function to allow modification of a passed
+ mutable buffer (for details see the reference documentation).
+
+- Made user requested changes to the itertools module.
+ Subsumed the times() function into repeat().
+ Added chain() and cycle().
+
+- The rotor module is now deprecated; the encryption algorithm it uses
+ is not believed to be secure, and including crypto code with Python
+ has implications for exporting and importing it in various countries.
+
+- The socket module now always uses the _socketobject wrapper class, even on
+ platforms which have dup(2). The makefile() method is built directly
+ on top of the socket without duplicating the file descriptor, allowing
+ timeouts to work properly.
+
+Library
+-------
+
+- New generator function os.walk() is an easy-to-use alternative to
+ os.path.walk(). See os module docs for details. os.path.walk()
+ isn't deprecated at this time, but may become deprecated in a
+ future release.
+
+- Added new module "platform" which provides a wide range of tools
+ for querying platform dependent features.
+
+- netrc now allows ASCII punctuation characters in passwords.
+
+- shelve now supports the optional writeback argument, and exposes
+ pickle protocol versions.
+
+- Several methods of nntplib.NNTP have grown an optional file argument
+ which specifies a file where to divert the command's output
+ (already supported by the body() method). (SF patch #720468)
+
+- The self-documenting XML server library DocXMLRPCServer was added.
+
+- Support for internationalized domain names has been added through
+ the 'idna' and 'punycode' encodings, the 'stringprep' module, the
+ 'mkstringprep' tool, and enhancements to the socket and httplib
+ modules.
+
+- htmlentitydefs has two new dictionaries: name2codepoint maps
+ HTML entity names to Unicode codepoints (as integers).
+ codepoint2name is the reverse mapping. See SF patch #722017.
+
+- pdb has a new command, "debug", which lets you step through
+ arbitrary code from the debugger's (pdb) prompt.
+
+- unittest.failUnlessEqual and its equivalent unittest.assertEqual now
+ return 'not a == b' rather than 'a != b'. This gives the desired
+ result for classes that define __eq__ without defining __ne__.
+
+- sgmllib now supports SGML marked sections, in particular the
+ MS Office extensions.
+
+- The urllib module now offers support for the iterator protocol.
+ SF patch 698520 contributed by Brett Cannon.
+
+- New module timeit provides a simple framework for timing the
+ execution speed of expressions and statements.
+
+- sets.Set objects now support mixed-type __eq__ and __ne__, instead
+ of raising TypeError. If x is a Set object and y is a non-Set object,
+ x == y is False, and x != y is True. This is akin to the change made
+ for mixed-type comparisons of datetime objects in 2.3a2; more info
+ about the rationale is in the NEWS entry for that. See also SF bug
+ report <http://www.python.org/sf/693121>.
+
+- On Unix platforms, if os.listdir() is called with a Unicode argument,
+ it now returns Unicode strings. (This behavior was added earlier
+ to the Windows NT/2k/XP version of os.listdir().)
+
+- Distutils: both 'py_modules' and 'packages' keywords can now be specified
+ in core.setup(). Previously you could supply one or the other, but
+ not both of them. (SF patch #695090 from Bernhard Herzog)
+
+- New csv package makes it easy to read/write CSV files.
+
+- Module shlex has been extended to allow posix-like shell parsings,
+ including a split() function for easy spliting of quoted strings and
+ commands. An iterator interface was also implemented.
+
+Tools/Demos
+-----------
+
+- New script combinerefs.py helps analyze new PYTHONDUMPREFS output.
+ See the module docstring for details.
+
+Build
+-----
+
+- Fix problem building on OSF1 because the compiler only accepted
+ preprocessor directives that start in column 1. (SF bug #691793.)
+
+C API
+-----
+
+- Added PyGC_Collect(), equivalent to calling gc.collect().
+
+- PyThreadState_GetDict() was changed not to raise an exception or
+ issue a fatal error when no current thread state is available. This
+ makes it possible to print dictionaries when no thread is active.
+
+- LONG_LONG was renamed to PY_LONG_LONG. Extensions that use this and
+ need compatibility with previous versions can use this:
+
+ #ifndef PY_LONG_LONG
+ #define PY_LONG_LONG LONG_LONG
+ #endif
+
+- Added PyObject_SelfIter() to fill the tp_iter slot for the
+ typical case where the method returns its self argument.
+
+- The extended type structure used for heap types (new-style
+ classes defined by Python code using a class statement) is now
+ exported from object.h as PyHeapTypeObject. (SF patch #696193.)
+
+New platforms
+-------------
+
+None this time.
+
+Tests
+-----
+
+- test_timeout now requires -u network to be passed to regrtest to run.
+ See SF bug #692988.
+
+Windows
+-------
+
+- os.fsync() now exists on Windows, and calls the Microsoft _commit()
+ function.
+
+- New function winsound.MessageBeep() wraps the Win32 API
+ MessageBeep().
+
+Mac
+---
+
+- os.listdir() now returns Unicode strings on MacOS X when called with
+ a Unicode argument. See the general news item under "Library".
+
+- A new method MacOS.WMAvailable() returns true if it is safe to access
+ the window manager, false otherwise.
+
+- EasyDialogs dialogs are now movable-modal, and if the application is
+ currently in the background they will ask to be moved to the foreground
+ before displaying.
+
+- OSA Scripting support has improved a lot, and gensuitemodule.py can now
+ be used by mere mortals. The documentation is now also more or less
+ complete.
+
+- The IDE (in a framework build) now includes introductory documentation
+ in Apple Help Viewer format.
+
+
+What's New in Python 2.3 alpha 2?
+=================================
+
+*Release date: 19-Feb-2003*
+
+Core and builtins
+-----------------
+
+- Negative positions returned from PEP 293 error callbacks are now
+ treated as being relative to the end of the input string. Positions
+ that are out of bounds raise an IndexError.
+
+- sys.path[0] (the directory from which the script is loaded) is now
+ turned into an absolute pathname, unless it is the empty string.
+ (SF patch #664376.)
+
+- Finally fixed the bug in compile() and exec where a string ending
+ with an indented code block but no newline would raise SyntaxError.
+ This would have been a four-line change in parsetok.c... Except
+ codeop.py depends on this behavior, so a compilation flag had to be
+ invented that causes the tokenizer to revert to the old behavior;
+ this required extra changes to 2 .h files, 2 .c files, and 2 .py
+ files. (Fixes SF bug #501622.)
+
+- If a new-style class defines neither __new__ nor __init__, its
+ constructor would ignore all arguments. This is changed now: the
+ constructor refuses arguments in this case. This might break code
+ that worked under Python 2.2. The simplest fix is to add a no-op
+ __init__: ``def __init__(self, *args, **kw): pass``.
+
+- Through a bytecode optimizer bug (and I bet you didn't even know
+ Python *had* a bytecode optimizer :-), "unsigned" hex/oct constants
+ with a leading minus sign would come out with the wrong sign.
+ ("Unsigned" hex/oct constants are those with a face value in the
+ range sys.maxint+1 through sys.maxint*2+1, inclusive; these have
+ always been interpreted as negative numbers through sign folding.)
+ E.g. 0xffffffff is -1, and -(0xffffffff) is 1, but -0xffffffff would
+ come out as -4294967295. This was the case in Python 2.2 through
+ 2.2.2 and 2.3a1, and in Python 2.4 it will once again have that
+ value, but according to PEP 237 it really needs to be 1 now. This
+ will be backported to Python 2.2.3 a well. (SF #660455)
+
+- int(s, base) sometimes sign-folds hex and oct constants; it only
+ does this when base is 0 and s.strip() starts with a '0'. When the
+ sign is actually folded, as in int("0xffffffff", 0) on a 32-bit
+ machine, which returns -1, a FutureWarning is now issued; in Python
+ 2.4, this will return 4294967295L, as do int("+0xffffffff", 0) and
+ int("0xffffffff", 16) right now. (PEP 347)
+
+- super(X, x): x may now be a proxy for an X instance, i.e.
+ issubclass(x.__class__, X) but not issubclass(type(x), X).
+
+- isinstance(x, X): if X is a new-style class, this is now equivalent
+ to issubclass(type(x), X) or issubclass(x.__class__, X). Previously
+ only type(x) was tested. (For classic classes this was already the
+ case.)
+
+- compile(), eval() and the exec statement now fully support source code
+ passed as unicode strings.
+
+- int subclasses can be initialized with longs if the value fits in an int.
+ See SF bug #683467.
+
+- long(string, base) takes time linear in len(string) when base is a power
+ of 2 now. It used to take time quadratic in len(string).
+
+- filter returns now Unicode results for Unicode arguments.
+
+- raw_input can now return Unicode objects.
+
+- List objects' sort() method now accepts None as the comparison function.
+ Passing None is semantically identical to calling sort() with no
+ arguments.
+
+- Fixed crash when printing a subclass of str and __str__ returned self.
+ See SF bug #667147.
+
+- Fixed an invalid RuntimeWarning and an undetected error when trying
+ to convert a long integer into a float which couldn't fit.
+ See SF bug #676155.
+
+- Function objects now have a __module__ attribute that is bound to
+ the name of the module in which the function was defined. This
+ applies for C functions and methods as well as functions and methods
+ defined in Python. This attribute is used by pickle.whichmodule(),
+ which changes the behavior of whichmodule slightly. In Python 2.2
+ whichmodule() returns "__main__" for functions that are not defined
+ at the top-level of a module (examples: methods, nested functions).
+ Now whichmodule() will return the proper module name.
+
+Extension modules
+-----------------
+
+- operator.isNumberType() now checks that the object has a nb_int or
+ nb_float slot, rather than simply checking whether it has a non-NULL
+ tp_as_number pointer.
+
+- The imp module now has ways to acquire and release the "import
+ lock": imp.acquire_lock() and imp.release_lock(). Note: this is a
+ reentrant lock, so releasing the lock only truly releases it when
+ this is the last release_lock() call. You can check with
+ imp.lock_held(). (SF bug #580952 and patch #683257.)
+
+- Change to cPickle to match pickle.py (see below and PEP 307).
+
+- Fix some bugs in the parser module. SF bug #678518.
+
+- Thanks to Scott David Daniels, a subtle bug in how the zlib
+ extension implemented flush() was fixed. Scott also rewrote the
+ zlib test suite using the unittest module. (SF bug #640230 and
+ patch #678531.)
+
+- Added an itertools module containing high speed, memory efficient
+ looping constructs inspired by tools from Haskell and SML.
+
+- The SSL module now handles sockets with a timeout set correctly (SF
+ patch #675750, fixing SF bug #675552).
+
+- os/posixmodule has grown the sysexits.h constants (EX_OK and friends).
+
+- Fixed broken threadstate swap in readline that could cause fatal
+ errors when a readline hook was being invoked while a background
+ thread was active. (SF bugs #660476 and #513033.)
+
+- fcntl now exposes the strops.h I_* constants.
+
+- Fix a crash on Solaris that occurred when calling close() on
+ an mmap'ed file which was already closed. (SF patch #665913)
+
+- Fixed several serious bugs in the zipimport implementation.
+
+- datetime changes:
+
+ The date class is now properly subclassable. (SF bug #720908)
+
+ The datetime and datetimetz classes have been collapsed into a single
+ datetime class, and likewise the time and timetz classes into a single
+ time class. Previously, a datetimetz object with tzinfo=None acted
+ exactly like a datetime object, and similarly for timetz. This wasn't
+ enough of a difference to justify distinct classes, and life is simpler
+ now.
+
+ today() and now() now round system timestamps to the closest
+ microsecond <http://www.python.org/sf/661086>. This repairs an
+ irritation most likely seen on Windows systems.
+
+ In dt.astimezone(tz), if tz.utcoffset(dt) returns a duration,
+ ValueError is raised if tz.dst(dt) returns None (2.3a1 treated it
+ as 0 instead, but a tzinfo subclass wishing to participate in
+ time zone conversion has to take a stand on whether it supports
+ DST; if you don't care about DST, then code dst() to return 0 minutes,
+ meaning that DST is never in effect).
+
+ The tzinfo methods utcoffset() and dst() must return a timedelta object
+ (or None) now. In 2.3a1 they could also return an int or long, but that
+ was an unhelpfully redundant leftover from an earlier version wherein
+ they couldn't return a timedelta. TOOWTDI.
+
+ The example tzinfo class for local time had a bug. It was replaced
+ by a later example coded by Guido.
+
+ datetime.astimezone(tz) no longer raises an exception when the
+ input datetime has no UTC equivalent in tz. For typical "hybrid" time
+ zones (a single tzinfo subclass modeling both standard and daylight
+ time), this case can arise one hour per year, at the hour daylight time
+ ends. See new docs for details. In short, the new behavior mimics
+ the local wall clock's behavior of repeating an hour in local time.
+
+ dt.astimezone() can no longer be used to convert between naive and aware
+ datetime objects. If you merely want to attach, or remove, a tzinfo
+ object, without any conversion of date and time members, use
+ dt.replace(tzinfo=whatever) instead, where "whatever" is None or a
+ tzinfo subclass instance.
+
+ A new method tzinfo.fromutc(dt) can be overridden in tzinfo subclasses
+ to give complete control over how a UTC time is to be converted to
+ a local time. The default astimezone() implementation calls fromutc()
+ as its last step, so a tzinfo subclass can affect that too by overriding
+ fromutc(). It's expected that the default fromutc() implementation will
+ be suitable as-is for "almost all" time zone subclasses, but the
+ creativity of political time zone fiddling appears unbounded -- fromutc()
+ allows the highly motivated to emulate any scheme expressible in Python.
+
+ datetime.now(): The optional tzinfo argument was undocumented (that's
+ repaired), and its name was changed to tz ("tzinfo" is overloaded enough
+ already). With a tz argument, now(tz) used to return the local date
+ and time, and attach tz to it, without any conversion of date and time
+ members. This was less than useful. Now now(tz) returns the current
+ date and time as local time in tz's time zone, akin to ::
+
+ tz.fromutc(datetime.utcnow().replace(tzinfo=utc))
+
+ where "utc" is an instance of a tzinfo subclass modeling UTC. Without
+ a tz argument, now() continues to return the current local date and time,
+ as a naive datetime object.
+
+ datetime.fromtimestamp(): Like datetime.now() above, this had less than
+ useful behavior when the optional tinzo argument was specified. See
+ also SF bug report <http://www.python.org/sf/660872>.
+
+ date and datetime comparison: In order to prevent comparison from
+ falling back to the default compare-object-addresses strategy, these
+ raised TypeError whenever they didn't understand the other object type.
+ They still do, except when the other object has a "timetuple" attribute,
+ in which case they return NotImplemented now. This gives other
+ datetime objects (e.g., mxDateTime) a chance to intercept the
+ comparison.
+
+ date, time, datetime and timedelta comparison: When the exception
+ for mixed-type comparisons in the last paragraph doesn't apply, if
+ the comparison is == then False is returned, and if the comparison is
+ != then True is returned. Because dict lookup and the "in" operator
+ only invoke __eq__, this allows, for example, ::
+
+ if some_datetime in some_sequence:
+
+ and ::
+
+ some_dict[some_timedelta] = whatever
+
+ to work as expected, without raising TypeError just because the
+ sequence is heterogeneous, or the dict has mixed-type keys. [This
+ seems like a good idea to implement for all mixed-type comparisons
+ that don't want to allow falling back to address comparison.]
+
+ The constructors building a datetime from a timestamp could raise
+ ValueError if the platform C localtime()/gmtime() inserted "leap
+ seconds". Leap seconds are ignored now. On such platforms, it's
+ possible to have timestamps that differ by a second, yet where
+ datetimes constructed from them are equal.
+
+ The pickle format of date, time and datetime objects has changed
+ completely. The undocumented pickler and unpickler functions no
+ longer exist. The undocumented __setstate__() and __getstate__()
+ methods no longer exist either.
+
+Library
+-------
+
+- The logging module was updated slightly; the WARN level was renamed
+ to WARNING, and the matching function/method warn() to warning().
+
+- The pickle and cPickle modules were updated with a new pickling
+ protocol (documented by pickletools.py, see below) and several
+ extensions to the pickle customization API (__reduce__, __setstate__
+ etc.). The copy module now uses more of the pickle customization
+ API to copy objects that don't implement __copy__ or __deepcopy__.
+ See PEP 307 for details.
+
+- The distutils "register" command now uses http://www.python.org/pypi
+ as the default repository. (See PEP 301.)
+
+- the platform dependent path related variables sep, altsep, extsep,
+ pathsep, curdir, pardir and defpath are now defined in the platform
+ dependent path modules (e.g. ntpath.py) rather than os.py, so these
+ variables are now available via os.path. They continue to be
+ available from the os module.
+ (see <http://www.python.org/sf/680789>).
+
+- array.array was added to the types repr.py knows about (see
+ <http://www.python.org/sf/680789>).
+
+- The new pickletools.py contains lots of documentation about pickle
+ internals, and supplies some helpers for working with pickles, such as
+ a symbolic pickle disassembler.
+
+- Xmlrpclib.py now supports the builtin boolean type.
+
+- py_compile has a new 'doraise' flag and a new PyCompileError
+ exception.
+
+- SimpleXMLRPCServer now supports CGI through the CGIXMLRPCRequestHandler
+ class.
+
+- The sets module now raises TypeError in __cmp__, to clarify that
+ sets are not intended to be three-way-compared; the comparison
+ operators are overloaded as subset/superset tests.
+
+- Bastion.py and rexec.py are disabled. These modules are not safe in
+ Python 2.2. or 2.3.
+
+- realpath is now exported when doing ``from poxixpath import *``.
+ It is also exported for ntpath, macpath, and os2emxpath.
+ See SF bug #659228.
+
+- New module tarfile from Lars Gustäbel provides a comprehensive interface
+ to tar archive files with transparent gzip and bzip2 compression.
+ See SF patch #651082.
+
+- urlparse can now parse imap:// URLs. See SF feature request #618024.
+
+- Tkinter.Canvas.scan_dragto() provides an optional parameter to support
+ the gain value which is passed to Tk. SF bug# 602259.
+
+- Fix logging.handlers.SysLogHandler protocol when using UNIX domain sockets.
+ See SF patch #642974.
+
+- The dospath module was deleted. Use the ntpath module when manipulating
+ DOS paths from other platforms.
+
+Tools/Demos
+-----------
+
+- Two new scripts (db2pickle.py and pickle2db.py) were added to the
+ Tools/scripts directory to facilitate conversion from the old bsddb module
+ to the new one. While the user-visible API of the new module is
+ compatible with the old one, it's likely that the version of the
+ underlying database library has changed. To convert from the old library,
+ run the db2pickle.py script using the old version of Python to convert it
+ to a pickle file. After upgrading Python, run the pickle2db.py script
+ using the new version of Python to reconstitute your database. For
+ example:
+
+ % python2.2 db2pickle.py -h some.db > some.pickle
+ % python2.3 pickle2db.py -h some.db.new < some.pickle
+
+ Run the scripts without any args to get a usage message.
+
+
+Build
+-----
+
+- The audio driver tests (test_ossaudiodev.py and
+ test_linuxaudiodev.py) are no longer run by default. This is
+ because they don't always work, depending on your hardware and
+ software. To run these tests, you must use an invocation like ::
+
+ ./python Lib/test/regrtest.py -u audio test_ossaudiodev
+
+- On systems which build using the configure script, compiler flags which
+ used to be lumped together using the OPT flag have been split into two
+ groups, OPT and BASECFLAGS. OPT is meant to carry just optimization- and
+ debug-related flags like "-g" and "-O3". BASECFLAGS is meant to carry
+ compiler flags that are required to get a clean compile. On some
+ platforms (many Linux flavors in particular) BASECFLAGS will be empty by
+ default. On others, such as Mac OS X and SCO, it will contain required
+ flags. This change allows people building Python to override OPT without
+ fear of clobbering compiler flags which are required to get a clean build.
+
+- On Darwin/Mac OS X platforms, /sw/lib and /sw/include are added to the
+ relevant search lists in setup.py. This allows users building Python to
+ take advantage of the many packages available from the fink project
+ <http://fink.sf.net/>.
+
+- A new Makefile target, scriptsinstall, installs a number of useful scripts
+ from the Tools/scripts directory.
+
+C API
+-----
+
+- PyEval_GetFrame() is now declared to return a ``PyFrameObject *``
+ instead of a plain ``PyObject *``. (SF patch #686601.)
+
+- PyNumber_Check() now checks that the object has a nb_int or nb_float
+ slot, rather than simply checking whether it has a non-NULL
+ tp_as_number pointer.
+
+- A C type that inherits from a base type that defines tp_as_buffer
+ will now inherit the tp_as_buffer pointer if it doesn't define one.
+ (SF #681367)
+
+- The PyArg_Parse functions now issue a DeprecationWarning if a float
+ argument is provided when an integer is specified (this affects the 'b',
+ 'B', 'h', 'H', 'i', and 'l' codes). Future versions of Python will
+ raise a TypeError.
+
+Tests
+-----
+
+- Several tests weren't being run from regrtest.py (test_timeout.py,
+ test_tarfile.py, test_netrc.py, test_multifile.py,
+ test_importhooks.py and test_imp.py). Now they are. (Note to
+ developers: please read Lib/test/README when creating a new test, to
+ make sure to do it right! All tests need to use either unittest or
+ pydoc.)
+
+- Added test_posix.py, a test suite for the posix module.
+
+- Added test_hexoct.py, a test suite for hex/oct constant folding.
+
+Windows
+-------
+
+- The timeout code for socket connect() didn't work right; this has
+ now been fixed. test_timeout.py should pass (at least most of the
+ time).
+
+- distutils' msvccompiler class now passes the preprocessor options to
+ the resource compiler. See SF patch #669198.
+
+- The bsddb module now ships with Sleepycat's 4.1.25.NC, the latest
+ release without strong cryptography.
+
+- sys.path[0], if it contains a directory name, is now always an
+ absolute pathname. (SF patch #664376.)
+
+- The new logging package is now installed by the Windows installer. It
+ wasn't in 2.3a1 due to oversight.
+
+Mac
+---
+
+- There are new dialogs EasyDialogs.AskFileForOpen, AskFileForSave
+ and AskFolder. The old macfs.StandardGetFile and friends are deprecated.
+
+- Most of the standard library now uses pathnames or FSRefs in preference
+ of FSSpecs, and use the underlying Carbon.File and Carbon.Folder modules
+ in stead of macfs. macfs will probably be deprecated in the future.
+
+- Type Carbon.File.FSCatalogInfo and supporting methods have been implemented.
+ This also makes macfs.FSSpec.SetDates() work again.
+
+- There is a new module pimp, the package install manager for Python, and
+ accompanying applet PackageManager. These allow you to easily download
+ and install pretested extension packages either in source or binary
+ form. Only in MacPython-OSX.
+
+- Applets are now built with bundlebuilder in MacPython-OSX, which should make
+ them more robust and also provides a path towards BuildApplication. The
+ downside of this change is that applets can no longer be run from the
+ Terminal window, this will hopefully be fixed in the 2.3b1.
+
+
+What's New in Python 2.3 alpha 1?
+=================================
+
+*Release date: 31-Dec-2002*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- One can now assign to __bases__ and __name__ of new-style classes.
+
+- dict() now accepts keyword arguments so that dict(one=1, two=2)
+ is the equivalent of {"one": 1, "two": 2}. Accordingly,
+ the existing (but undocumented) 'items' keyword argument has
+ been eliminated. This means that dict(items=someMapping) now has
+ a different meaning than before.
+
+- int() now returns a long object if the argument is outside the
+ integer range, so int("4" * 1000), int(1e200) and int(1L<<1000) will
+ all return long objects instead of raising an OverflowError.
+
+- Assignment to __class__ is disallowed if either the old or the new
+ class is a statically allocated type object (such as defined by an
+ extension module). This prevents anomalies like 2.__class__ = bool.
+
+- New-style object creation and deallocation have been sped up
+ significantly; they are now faster than classic instance creation
+ and deallocation.
+
+- The __slots__ variable can now mention "private" names, and the
+ right thing will happen (e.g. __slots__ = ["__foo"]).
+
+- The built-ins slice() and buffer() are now callable types. The
+ types classobj (formerly class), code, function, instance, and
+ instancemethod (formerly instance-method), which have no built-in
+ names but are accessible through the types module, are now also
+ callable. The type dict-proxy is renamed to dictproxy.
+
+- Cycles going through the __class__ link of a new-style instance are
+ now detected by the garbage collector.
+
+- Classes using __slots__ are now properly garbage collected.
+ [SF bug 519621]
+
+- Tightened the __slots__ rules: a slot name must be a valid Python
+ identifier.
+
+- The constructor for the module type now requires a name argument and
+ takes an optional docstring argument. Previously, this constructor
+ ignored its arguments. As a consequence, deriving a class from a
+ module (not from the module type) is now illegal; previously this
+ created an unnamed module, just like invoking the module type did.
+ [SF bug 563060]
+
+- A new type object, 'basestring', is added. This is a common base type
+ for 'str' and 'unicode', and can be used instead of
+ types.StringTypes, e.g. to test whether something is "a string":
+ isinstance(x, basestring) is True for Unicode and 8-bit strings. This
+ is an abstract base class and cannot be instantiated directly.
+
+- Changed new-style class instantiation so that when C's __new__
+ method returns something that's not a C instance, its __init__ is
+ not called. [SF bug #537450]
+
+- Fixed super() to work correctly with class methods. [SF bug #535444]
+
+- If you try to pickle an instance of a class that has __slots__ but
+ doesn't define or override __getstate__, a TypeError is now raised.
+ This is done by adding a bozo __getstate__ to the class that always
+ raises TypeError. (Before, this would appear to be pickled, but the
+ state of the slots would be lost.)
+
+Core and builtins
+-----------------
+
+- Import from zipfiles is now supported. The name of a zipfile placed
+ on sys.path causes the import statement to look for importable Python
+ modules (with .py, pyc and .pyo extensions) and packages inside the
+ zipfile. The zipfile import follows the specification (though not
+ the sample implementation) of PEP 273. The semantics of __path__ are
+ compatible with those that have been implemented in Jython since
+ Jython 2.1.
+
+- PEP 302 has been accepted. Although it was initially developed to
+ support zipimport, it offers a new, general import hook mechanism.
+ Several new variables have been added to the sys module:
+ sys.meta_path, sys.path_hooks, and sys.path_importer_cache; these
+ make extending the import statement much more convenient than
+ overriding the __import__ built-in function. For a description of
+ these, see PEP 302.
+
+- A frame object's f_lineno attribute can now be written to from a
+ trace function to change which line will execute next. A command to
+ exploit this from pdb has been added. [SF patch #643835]
+
+- The _codecs support module for codecs.py was turned into a builtin
+ module to assure that at least the builtin codecs are available
+ to the Python parser for source code decoding according to PEP 263.
+
+- issubclass now supports a tuple as the second argument, just like
+ isinstance does. ``issubclass(X, (A, B))`` is equivalent to
+ ``issubclass(X, A) or issubclass(X, B)``.
+
+- Thanks to Armin Rigo, the last known way to provoke a system crash
+ by cleverly arranging for a comparison function to mutate a list
+ during a list.sort() operation has been fixed. The effect of
+ attempting to mutate a list, or even to inspect its contents or
+ length, while a sort is in progress, is not defined by the language.
+ The C implementation of Python 2.3 attempts to detect mutations,
+ and raise ValueError if one occurs, but there's no guarantee that
+ all mutations will be caught, or that any will be caught across
+ releases or implementations.
+
+- Unicode file name processing for Windows (PEP 277) is implemented.
+ All platforms now have an os.path.supports_unicode_filenames attribute,
+ which is set to True on Windows NT/2000/XP, and False elsewhere.
+
+- Codec error handling callbacks (PEP 293) are implemented.
+ Error handling in unicode.encode or str.decode can now be customized.
+
+- A subtle change to the semantics of the built-in function intern():
+ interned strings are no longer immortal. You must keep a reference
+ to the return value intern() around to get the benefit.
+
+- Use of 'None' as a variable, argument or attribute name now
+ issues a SyntaxWarning. In the future, None may become a keyword.
+
+- SET_LINENO is gone. co_lnotab is now consulted to determine when to
+ call the trace function. C code that accessed f_lineno should call
+ PyCode_Addr2Line instead (f_lineno is still there, but only kept up
+ to date when there is a trace function set).
+
+- There's a new warning category, FutureWarning. This is used to warn
+ about a number of situations where the value or sign of an integer
+ result will change in Python 2.4 as a result of PEP 237 (integer
+ unification). The warnings implement stage B0 mentioned in that
+ PEP. The warnings are about the following situations:
+
+ - Octal and hex literals without 'L' prefix in the inclusive range
+ [0x80000000..0xffffffff]; these are currently negative ints, but
+ in Python 2.4 they will be positive longs with the same bit
+ pattern.
+
+ - Left shifts on integer values that cause the outcome to lose
+ bits or have a different sign than the left operand. To be
+ precise: x<<n where this currently doesn't yield the same value
+ as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
+
+ - Conversions from ints to string that show negative values as
+ unsigned ints in the inclusive range [0x80000000..0xffffffff];
+ this affects the functions hex() and oct(), and the string
+ formatting codes %u, %o, %x, and %X. In Python 2.4, these will
+ show signed values (e.g. hex(-1) currently returns "0xffffffff";
+ in Python 2.4 it will return "-0x1").
+
+- The bits manipulated under the cover by sys.setcheckinterval() have
+ been changed. Both the check interval and the ticker used to be
+ per-thread values. They are now just a pair of global variables.
+ In addition, the default check interval was boosted from 10 to 100
+ bytecode instructions. This may have some effect on systems that
+ relied on the old default value. In particular, in multi-threaded
+ applications which try to be highly responsive, response time will
+ increase by some (perhaps imperceptible) amount.
+
+- When multiplying very large integers, a version of the so-called
+ Karatsuba algorithm is now used. This is most effective if the
+ inputs have roughly the same size. If they both have about N digits,
+ Karatsuba multiplication has O(N**1.58) runtime (the exponent is
+ log_base_2(3)) instead of the previous O(N**2). Measured results may
+ be better or worse than that, depending on platform quirks. Besides
+ the O() improvement in raw instruction count, the Karatsuba algorithm
+ appears to have much better cache behavior on extremely large integers
+ (starting in the ballpark of a million bits). Note that this is a
+ simple implementation, and there's no intent here to compete with,
+ e.g., GMP. It gives a very nice speedup when it applies, but a package
+ devoted to fast large-integer arithmetic should run circles around it.
+
+- u'%c' will now raise a ValueError in case the argument is an
+ integer outside the valid range of Unicode code point ordinals.
+
+- The tempfile module has been overhauled for enhanced security. The
+ mktemp() function is now deprecated; new, safe replacements are
+ mkstemp() (for files) and mkdtemp() (for directories), and the
+ higher-level functions NamedTemporaryFile() and TemporaryFile().
+ Use of some global variables in this module is also deprecated; the
+ new functions have keyword arguments to provide the same
+ functionality. All Lib, Tools and Demo modules that used the unsafe
+ interfaces have been updated to use the safe replacements. Thanks
+ to Zack Weinberg!
+
+- When x is an object whose class implements __mul__ and __rmul__,
+ 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
+ invoke __mul__. This was due to the sequence-repeat code in the int
+ type. This has been fixed now.
+
+- Previously, "str1 in str2" required str1 to be a string of length 1.
+ This restriction has been relaxed to allow str1 to be a string of
+ any length. Thus "'el' in 'hello world'" returns True now.
+
+- File objects are now their own iterators. For a file f, iter(f) now
+ returns f (unless f is closed), and f.next() is similar to
+ f.readline() when EOF is not reached; however, f.next() uses a
+ readahead buffer that messes up the file position, so mixing
+ f.next() and f.readline() (or other methods) doesn't work right.
+ Calling f.seek() drops the readahead buffer, but other operations
+ don't. It so happens that this gives a nice additional speed boost
+ to "for line in file:"; the xreadlines method and corresponding
+ module are now obsolete. Thanks to Oren Tirosh!
+
+- Encoding declarations (PEP 263, phase 1) have been implemented. A
+ comment of the form "# -*- coding: <encodingname> -*-" in the first
+ or second line of a Python source file indicates the encoding.
+
+- list.sort() has a new implementation. While cross-platform results
+ may vary, and in data-dependent ways, this is much faster on many
+ kinds of partially ordered lists than the previous implementation,
+ and reported to be just as fast on randomly ordered lists on
+ several major platforms. This sort is also stable (if A==B and A
+ precedes B in the list at the start, A precedes B after the sort too),
+ although the language definition does not guarantee stability. A
+ potential drawback is that list.sort() may require temp space of
+ len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
+ for list.sort() to raise MemoryError now, even if a comparison function
+ does not. See <http://www.python.org/sf/587076> for full details.
+
+- All standard iterators now ensure that, once StopIteration has been
+ raised, all future calls to next() on the same iterator will also
+ raise StopIteration. There used to be various counterexamples to
+ this behavior, which could caused confusion or subtle program
+ breakage, without any benefits. (Note that this is still an
+ iterator's responsibility; the iterator framework does not enforce
+ this.)
+
+- Ctrl+C handling on Windows has been made more consistent with
+ other platforms. KeyboardInterrupt can now reliably be caught,
+ and Ctrl+C at an interactive prompt no longer terminates the
+ process under NT/2k/XP (it never did under Win9x). Ctrl+C will
+ interrupt time.sleep() in the main thread, and any child processes
+ created via the popen family (on win2k; we can't make win9x work
+ reliably) are also interrupted (as generally happens on for Linux/Unix.)
+ [SF bugs 231273, 439992 and 581232]
+
+- sys.getwindowsversion() has been added on Windows. This
+ returns a tuple with information about the version of Windows
+ currently running.
+
+- Slices and repetitions of buffer objects now consistently return
+ a string. Formerly, strings would be returned most of the time,
+ but a buffer object would be returned when the repetition count
+ was one or when the slice range was all inclusive.
+
+- Unicode objects in sys.path are no longer ignored but treated
+ as directory names.
+
+- Fixed string.startswith and string.endswith builtin methods
+ so they accept negative indices. [SF bug 493951]
+
+- Fixed a bug with a continue inside a try block and a yield in the
+ finally clause. [SF bug 567538]
+
+- Most builtin sequences now support "extended slices", i.e. slices
+ with a third "stride" parameter. For example, "hello world"[::-1]
+ gives "dlrow olleh".
+
+- A new warning PendingDeprecationWarning was added to provide
+ direction on features which are in the process of being deprecated.
+ The warning will not be printed by default. To see the pending
+ deprecations, use -Walways::PendingDeprecationWarning::
+ as a command line option or warnings.filterwarnings() in code.
+
+- Deprecated features of xrange objects have been removed as
+ promised. The start, stop, and step attributes and the tolist()
+ method no longer exist. xrange repetition and slicing have been
+ removed.
+
+- New builtin function enumerate(x), from PEP 279. Example:
+ enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
+ The argument can be an arbitrary iterable object.
+
+- The assert statement no longer tests __debug__ at runtime. This means
+ that assert statements cannot be disabled by assigning a false value
+ to __debug__.
+
+- A method zfill() was added to str and unicode, that fills a numeric
+ string to the left with zeros. For example,
+ "+123".zfill(6) -> "+00123".
+
+- Complex numbers supported divmod() and the // and % operators, but
+ these make no sense. Since this was documented, they're being
+ deprecated now.
+
+- String and unicode methods lstrip(), rstrip() and strip() now take
+ an optional argument that specifies the characters to strip. For
+ example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
+
+- There's a new dictionary constructor (a class method of the dict
+ class), dict.fromkeys(iterable, value=None). It constructs a
+ dictionary with keys taken from the iterable and all values set to a
+ single value. It can be used for building sets and for removing
+ duplicates from sequences.
+
+- Added a new dict method pop(key). This removes and returns the
+ value corresponding to key. [SF patch #539949]
+
+- A new built-in type, bool, has been added, as well as built-in
+ names for its two values, True and False. Comparisons and sundry
+ other operations that return a truth value have been changed to
+ return a bool instead. Read PEP 285 for an explanation of why this
+ is backward compatible.
+
+- Fixed two bugs reported as SF #535905: under certain conditions,
+ deallocating a deeply nested structure could cause a segfault in the
+ garbage collector, due to interaction with the "trashcan" code;
+ access to the current frame during destruction of a local variable
+ could access a pointer to freed memory.
+
+- The optional object allocator ("pymalloc") has been enabled by
+ default. The recommended practice for memory allocation and
+ deallocation has been streamlined. A header file is included,
+ Misc/pymemcompat.h, which can be bundled with 3rd party extensions
+ and lets them use the same API with Python versions from 1.5.2
+ onwards.
+
+- PyErr_Display will provide file and line information for all exceptions
+ that have an attribute print_file_and_line, not just SyntaxErrors.
+
+- The UTF-8 codec will now encode and decode Unicode surrogates
+ correctly and without raising exceptions for unpaired ones.
+
+- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
+ instead of 'r' when opening a text file for reading changes the line
+ ending convention so that any of '\r', '\r\n', and '\n' is
+ recognized (even mixed in one file); all three are converted to
+ '\n', the standard Python line end character.
+
+- file.xreadlines() now raises a ValueError if the file is closed:
+ Previously, an xreadlines object was returned which would raise
+ a ValueError when the xreadlines.next() method was called.
+
+- sys.exit() inadvertently allowed more than one argument.
+ An exception will now be raised if more than one argument is used.
+
+- Changed evaluation order of dictionary literals to conform to the
+ general left to right evaluation order rule. Now {f1(): f2()} will
+ evaluate f1 first.
+
+- Fixed bug #521782: when a file was in non-blocking mode, file.read()
+ could silently lose data or wrongly throw an unknown error.
+
+- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
+ slots are now always tried after trying the corresponding nb_* slots.
+ This fixes a number of minor bugs (see bug #624807).
+
+- Fix problem with dynamic loading on 64-bit AIX (see bug #639945).
+
+Extension modules
+-----------------
+
+- Added three operators to the operator module:
+ operator.pow(a,b) which is equivalent to: a**b.
+ operator.is_(a,b) which is equivalent to: a is b.
+ operator.is_not(a,b) which is equivalent to: a is not b.
+
+- posix.openpty now works on all systems that have /dev/ptmx.
+
+- A module zipimport exists to support importing code from zip
+ archives.
+
+- The new datetime module supplies classes for manipulating dates and
+ times. The basic design came from the Zope "fishbowl process", and
+ favors practical commercial applications over calendar esoterica. See
+
+ http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
+
+- _tkinter now returns Tcl objects, instead of strings. Objects which
+ have Python equivalents are converted to Python objects, other objects
+ are wrapped. This can be configured through the wantobjects method,
+ or Tkinter.wantobjects.
+
+- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
+ been added as the package bsddb. The traditional bsddb module is
+ still available in source code, but not built automatically anymore,
+ and is now named bsddb185. This supports Berkeley DB versions from
+ 3.0 to 4.1. For help converting your databases from the old module (which
+ probably used an obsolete version of Berkeley DB) to the new module, see
+ the db2pickle.py and pickle2db.py scripts described in the Tools/Demos
+ section above.
+
+- unicodedata was updated to Unicode 3.2. It supports normalization
+ and names for Hangul syllables and CJK unified ideographs.
+
+- resource.getrlimit() now returns longs instead of ints.
+
+- readline now dynamically adjusts its input/output stream if
+ sys.stdin/stdout changes.
+
+- The _tkinter module (and hence Tkinter) has dropped support for
+ Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
+ supported.
+
+- cPickle.BadPickleGet is now a class.
+
+- The time stamps in os.stat_result are floating point numbers
+ after stat_float_times has been called.
+
+- If the size passed to mmap.mmap() is larger than the length of the
+ file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
+
+- The xreadlines module is slated for obsolescence.
+
+- The strptime function in the time module is now always available (a
+ Python implementation is used when the C library doesn't define it).
+
+- The 'new' module is no longer an extension, but a Python module that
+ only exists for backwards compatibility. Its contents are no longer
+ functions but callable type objects.
+
+- The bsddb.*open functions can now take 'None' as a filename.
+ This will create a temporary in-memory bsddb that won't be
+ written to disk.
+
+- posix.getloadavg, posix.lchown, posix.killpg, posix.mknod, and
+ posix.getpgid have been added where available.
+
+- The locale module now exposes the C library's gettext interface. It
+ also has a new function getpreferredencoding.
+
+- A security hole ("double free") was found in zlib-1.1.3, a popular
+ third party compression library used by some Python modules. The
+ hole was quickly plugged in zlib-1.1.4, and the Windows build of
+ Python now ships with zlib-1.1.4.
+
+- pwd, grp, and resource return enhanced tuples now, with symbolic
+ field names.
+
+- array.array is now a type object. A new format character
+ 'u' indicates Py_UNICODE arrays. For those, .tounicode and
+ .fromunicode methods are available. Arrays now support __iadd__
+ and __imul__.
+
+- dl now builds on every system that has dlfcn.h. Failure in case
+ of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
+ is called.
+
+- The sys module acquired a new attribute, api_version, which evaluates
+ to the value of the PYTHON_API_VERSION macro with which the
+ interpreter was compiled.
+
+- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
+ when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
+ returns (None, None, 'ab'), as expected. Also fixed handling of
+ lastindex/lastgroup match attributes in similar cases. For example,
+ when running the expression r'(a)(b)?b' over 'ab', lastindex must be
+ 1, not 2.
+
+- Fixed bug #581080: sre scanner was not checking the buffer limit
+ before increasing the current pointer. This was creating an infinite
+ loop in the search function, once the pointer exceeded the buffer
+ limit.
+
+- The os.fdopen function now enforces a file mode starting with the
+ letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
+ bug #623464.
+
+- The linuxaudiodev module is now deprecated; it is being replaced by
+ ossaudiodev. The interface has been extended to cover a lot more of
+ OSS (see www.opensound.com), including most DSP ioctls and the
+ OSS mixer API. Documentation forthcoming in 2.3a2.
+
+Library
+-------
+
+- imaplib.py now supports SSL (Tino Lange and Piers Lauder).
+
+- Freeze's modulefinder.py has been moved to the standard library;
+ slightly improved so it will issue less false missing submodule
+ reports (see sf path #643711 for details). Documentation will follow
+ with Python 2.3a2.
+
+- os.path exposes getctime.
+
+- unittest.py now has two additional methods called assertAlmostEqual()
+ and failIfAlmostEqual(). They implement an approximate comparison
+ by rounding the difference between the two arguments and comparing
+ the result to zero. Approximate comparison is essential for
+ unit tests of floating point results.
+
+- calendar.py now depends on the new datetime module rather than
+ the time module. As a result, the range of allowable dates
+ has been increased.
+
+- pdb has a new 'j(ump)' command to select the next line to be
+ executed.
+
+- The distutils created windows installers now can run a
+ postinstallation script.
+
+- doctest.testmod can now be called without argument, which means to
+ test the current module.
+
+- When canceling a server that implemented threading with a keyboard
+ interrupt, the server would shut down but not terminate (waiting on
+ client threads). A new member variable, daemon_threads, was added to
+ the ThreadingMixIn class in SocketServer.py to make it explicit that
+ this behavior needs to be controlled.
+
+- A new module, optparse, provides a fancy alternative to getopt for
+ command line parsing. It is a slightly modified version of Greg
+ Ward's Optik package.
+
+- UserDict.py now defines a DictMixin class which defines all dictionary
+ methods for classes that already have a minimum mapping interface.
+ This greatly simplifies writing classes that need to be substitutable
+ for dictionaries (such as the shelve module).
+
+- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
+ all dictionary methods. This eases the transition to persistent
+ storage for scripts originally written with dictionaries in mind.
+
+- shelve.open and the various classes in shelve.py now accept an optional
+ binary flag, which defaults to False. If True, the values stored in the
+ shelf are binary pickles.
+
+- A new package, logging, implements the logging API defined by PEP
+ 282. The code is written by Vinay Sajip.
+
+- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
+ modules are iterators now.
+
+- gzip.py now handles files exceeding 2GB. Files over 4GB also work
+ now (provided the OS supports it, and Python is configured with large
+ file support), but in that case the underlying gzip file format can
+ record only the least-significant 32 bits of the file size, so that
+ some tools working with gzipped files may report an incorrect file
+ size.
+
+- xml.sax.saxutils.unescape has been added, to replace entity references
+ with their entity value.
+
+- Queue.Queue.{put,get} now support an optional timeout argument.
+
+- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
+ option of tkFileDialog is exposed as function askopenfile{,name}s.
+
+- Various configure methods of Tkinter have been stream-lined, so that
+ tag_configure, image_configure, window_configure now return a
+ dictionary when invoked with no argument.
+
+- Importing the readline module now no longer has the side effect of
+ calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
+ whatever locale is explicitly set by the user, is preserved. If you
+ want repr() of 8-bit strings in your preferred encoding to preserve
+ all printable characters of that encoding, you have to add the
+ following code to your $PYTHONSTARTUP file or to your application's
+ main():
+
+ import locale
+ locale.setlocale(locale.LC_CTYPE, "")
+
+- shutil.move was added. shutil.copytree now reports errors as an
+ exception at the end, instead of printing error messages.
+
+- Encoding name normalization was generalized to not only
+ replace hyphens with underscores, but also all other non-alphanumeric
+ characters (with the exception of the dot which is used for Python
+ package names during lookup). The aliases.py mapping was updated
+ to the new standard.
+
+- mimetypes has two new functions: guess_all_extensions() which
+ returns a list of all known extensions for a mime type, and
+ add_type() which adds one mapping between a mime type and
+ an extension to the database.
+
+- New module: sets, defines the class Set that implements a mutable
+ set type using the keys of a dict to represent the set. There's
+ also a class ImmutableSet which is useful when you need sets of sets
+ or when you need to use sets as dict keys, and a class BaseSet which
+ is the base class of the two.
+
+- Added random.sample(population,k) for random sampling without replacement.
+ Returns a k length list of unique elements chosen from the population.
+
+- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
+ OverflowError. That is, it now accepts any combination of 'start'
+ and 'stop' arguments so long as each is in the range of Python's
+ bounded integers.
+
+- Thanks to Raymond Hettinger, random.random() now uses a new core
+ generator. The Mersenne Twister algorithm is implemented in C,
+ threadsafe, faster than the previous generator, has an astronomically
+ large period (2**19937-1), creates random floats to full 53-bit
+ precision, and may be the most widely tested random number generator
+ in existence.
+
+ The random.jumpahead(n) method has different semantics for the new
+ generator. Instead of jumping n steps ahead, it uses n and the
+ existing state to create a new state. This means that jumpahead()
+ continues to support multi-threaded code needing generators of
+ non-overlapping sequences. However, it will break code which relies
+ on jumpahead moving a specific number of steps forward.
+
+ The attributes random.whseed and random.__whseed have no meaning for
+ the new generator. Code using these attributes should switch to a
+ new class, random.WichmannHill which is provided for backward
+ compatibility and to make an alternate generator available.
+
+- New "algorithms" module: heapq, implements a heap queue. Thanks to
+ Kevin O'Connor for the code and François Pinard for an entertaining
+ write-up explaining the theory and practical uses of heaps.
+
+- New encoding for the Palm OS character set: palmos.
+
+- binascii.crc32() and the zipfile module had problems on some 64-bit
+ platforms. These have been fixed. On a platform with 8-byte C longs,
+ crc32() now returns a signed-extended 4-byte result, so that its value
+ as a Python int is equal to the value computed a 32-bit platform.
+
+- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
+ argument.
+
+- Some fixes in the copy module: when an object is copied through its
+ __reduce__ method, there was no check for a __setstate__ method on
+ the result [SF patch 565085]; deepcopy should treat instances of
+ custom metaclasses the same way it treats instances of type 'type'
+ [SF patch 560794].
+
+- Sockets now support timeout mode. After s.settimeout(T), where T is
+ a float expressing seconds, subsequent operations raise an exception
+ if they cannot be completed within T seconds. To disable timeout
+ mode, use s.settimeout(None). There's also a module function,
+ socket.setdefaulttimeout(T), which sets the default for all sockets
+ created henceforth.
+
+- getopt.gnu_getopt was added. This supports GNU-style option
+ processing, where options can be mixed with non-option arguments.
+
+- Stop using strings for exceptions. String objects used for
+ exceptions are now classes deriving from Exception. The objects
+ changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
+ tabnanny.NannyNag, and xdrlib.Error.
+
+- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
+ BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
+ Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
+ big endian systems were added to the codecs module. The old names
+ BOM32_* and BOM64_* were off by a factor of 2.
+
+- Added conversion functions math.degrees() and math.radians().
+
+- math.log() now takes an optional argument: math.log(x[, base]).
+
+- ftplib.retrlines() now tests for callback is None rather than testing
+ for False. Was causing an error when given a callback object which
+ was callable but also returned len() as zero. The change may
+ create new breakage if the caller relied on the undocumented behavior
+ and called with callback set to [] or some other False value not
+ identical to None.
+
+- random.gauss() uses a piece of hidden state used by nothing else,
+ and the .seed() and .whseed() methods failed to reset it. In other
+ words, setting the seed didn't completely determine the sequence of
+ results produced by random.gauss(). It does now. Programs repeatedly
+ mixing calls to a seed method with calls to gauss() may see different
+ results now.
+
+- The pickle.Pickler class grew a clear_memo() method to mimic that
+ provided by cPickle.Pickler.
+
+- difflib's SequenceMatcher class now does a dynamic analysis of
+ which elements are so frequent as to constitute noise. For
+ comparing files as sequences of lines, this generally works better
+ than the IS_LINE_JUNK function, and function ndiff's linejunk
+ argument defaults to None now as a result. A happy benefit is
+ that SequenceMatcher may run much faster now when applied
+ to large files with many duplicate lines (for example, C program
+ text with lots of repeated "}" and "return NULL;" lines).
+
+- New Text.dump() method in Tkinter module.
+
+- New distutils commands for building packagers were added to
+ support pkgtool on Solaris and swinstall on HP-UX.
+
+- distutils now has a new abstract binary packager base class
+ command/bdist_packager, which simplifies writing packagers.
+ This will hopefully provide the missing bits to encourage
+ people to submit more packagers, e.g. for Debian, FreeBSD
+ and other systems.
+
+- The UTF-16, -LE and -BE stream readers now raise a
+ NotImplementedError for all calls to .readline(). Previously, they
+ used to just produce garbage or fail with an encoding error --
+ UTF-16 is a 2-byte encoding and the C lib's line reading APIs don't
+ work well with these.
+
+- compileall now supports quiet operation.
+
+- The BaseHTTPServer now implements optional HTTP/1.1 persistent
+ connections.
+
+- socket module: the SSL support was broken out of the main
+ _socket module C helper and placed into a new _ssl helper
+ which now gets imported by socket.py if available and working.
+
+- encodings package: added aliases for all supported IANA character
+ sets
+
+- ftplib: to safeguard the user's privacy, anonymous login will use
+ "anonymous@" as default password, rather than the real user and host
+ name.
+
+- webbrowser: tightened up the command passed to os.system() so that
+ arbitrary shell code can't be executed because a bogus URL was
+ passed in.
+
+- gettext.translation has an optional fallback argument, and
+ gettext.find an optional all argument. Translations will now fallback
+ on a per-message basis. The module supports plural forms, by means
+ of gettext.[d]ngettext and Translation.[u]ngettext.
+
+- distutils bdist commands now offer a --skip-build option.
+
+- warnings.warn now accepts a Warning instance as first argument.
+
+- The xml.sax.expatreader.ExpatParser class will no longer create
+ circular references by using itself as the locator that gets passed
+ to the content handler implementation. [SF bug #535474]
+
+- The email.Parser.Parser class now properly parses strings regardless
+ of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
+ or CRLF). Also, the Header class's constructor default arguments
+ has changed slightly so that an explicit maxlinelen value is always
+ honored, and so unicode conversion error handling can be specified.
+
+- distutils' build_ext command now links C++ extensions with the C++
+ compiler available in the Makefile or CXX environment variable, if
+ running under \*nix.
+
+- New module bz2: provides a comprehensive interface for the bz2 compression
+ library. It implements a complete file interface, one-shot (de)compression
+ functions, and types for sequential (de)compression.
+
+- New pdb command 'pp' which is like 'p' except that it pretty-prints
+ the value of its expression argument.
+
+- Now bdist_rpm distutils command understands a verify_script option in
+ the config file, including the contents of the referred filename in
+ the "%verifyscript" section of the rpm spec file.
+
+- Fixed bug #495695: webbrowser module would run graphic browsers in a
+ unix environment even if DISPLAY was not set. Also, support for
+ skipstone browser was included.
+
+- Fixed bug #636769: rexec would run unallowed code if subclasses of
+ strings were used as parameters for certain functions.
+
+Tools/Demos
+-----------
+
+- pygettext.py now supports globbing on Windows, and accepts module
+ names in addition to accepting file names.
+
+- The SGI demos (Demo/sgi) have been removed. Nobody thought they
+ were interesting any more. (The SGI library modules and extensions
+ are still there; it is believed that at least some of these are
+ still used and useful.)
+
+- IDLE supports the new encoding declarations (PEP 263); it can also
+ deal with legacy 8-bit files if they use the locale's encoding. It
+ allows non-ASCII strings in the interactive shell and executes them
+ in the locale's encoding.
+
+- freeze.py now produces binaries which can import shared modules,
+ unlike before when this failed due to missing symbol exports in
+ the generated binary.
+
+Build
+-----
+
+- On Unix, IDLE is now installed automatically.
+
+- The fpectl module is not built by default; it's dangerous or useless
+ except in the hands of experts.
+
+- The public Python C API will generally be declared using PyAPI_FUNC
+ and PyAPI_DATA macros, while Python extension module init functions
+ will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
+ are deprecated.
+
+- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
+ get into infinite loops, when a new-style class got garbage-collected.
+ Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
+ that new-style classes be immortal in COUNT_ALLOCS builds. Note that
+ COUNT_ALLOCS is not enabled by default, in either release or debug
+ builds, and that new-style classes are immortal only in COUNT_ALLOCS
+ builds.
+
+- Compiling out the cyclic garbage collector is no longer an option.
+ The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
+ that it's always defined (for the benefit of any extension modules
+ that may be conditionalizing on it). A bonus is that any extension
+ type participating in cyclic gc can choose to participate in the
+ Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
+ to require editing the core to teach the trashcan mechanism about the
+ new type.
+
+- According to Annex F of the current C standard,
+
+ The Standard C macro HUGE_VAL and its float and long double analogs,
+ HUGE_VALF and HUGE_VALL, expand to expressions whose values are
+ positive infinities.
+
+ Python only uses the double HUGE_VAL, and only to #define its own symbol
+ Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
+ pyport.h used to try to worm around that, but the workarounds triggered
+ other bugs on other platforms, so we gave up. If your platform defines
+ HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
+ that works on your platform. The only instance of this I'm sure about
+ is on an unknown subset of Cray systems, described here:
+
+ http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
+
+ Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
+
+- The configure option --without-doc-strings can be used to remove the
+ doc strings from the builtin functions and modules; this reduces the
+ size of the executable.
+
+- The universal newlines option (PEP 278) is on by default. On Unix
+ it can be disabled by passing --without-universal-newlines to the
+ configure script. On other platforms, remove
+ WITH_UNIVERSAL_NEWLINES from pyconfig.h.
+
+- On Unix, a shared libpython2.3.so can be created with --enable-shared.
+
+- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
+ preprocessor symbols were eliminated. The internal decisions they
+ controlled stopped being experimental long ago.
+
+- The tools used to build the documentation now work under Cygwin as
+ well as Unix.
+
+- The bsddb and dbm module builds have been changed to try and avoid version
+ skew problems and disable linkage with Berkeley DB 1.85 unless the
+ installer knows what s/he's doing. See the section on building these
+ modules in the README file for details.
+
+C API
+-----
+
+- PyNumber_Check() now returns true for string and unicode objects.
+ This is a result of these types having a partially defined
+ tp_as_number slot. (This is not a feature, but an indication that
+ PyNumber_Check() is not very useful to determine numeric behavior.
+ It may be deprecated.)
+
+- The string object's layout has changed: the pointer member
+ ob_sinterned has been replaced by an int member ob_sstate. On some
+ platforms (e.g. most 64-bit systems) this may change the offset of
+ the ob_sval member, so as a precaution the API_VERSION has been
+ incremented. The apparently unused feature of "indirect interned
+ strings", supported by the ob_sinterned member, is gone. Interned
+ strings are now usually mortal; there is a new API,
+ PyString_InternImmortal() that creates immortal interned strings.
+ (The ob_sstate member can only take three values; however, while
+ making it a char saves a few bytes per string object on average, in
+ it also slowed things down a bit because ob_sval was no longer
+ aligned.)
+
+- The Py_InitModule*() functions now accept NULL for the 'methods'
+ argument. Modules without global functions are becoming more common
+ now that factories can be types rather than functions.
+
+- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
+ level.
+
+- New functions PyErr_SetExcFromWindowsErr() and
+ PyErr_SetExcFromWindowsErrWithFilename(). Similar to
+ PyErr_SetFromWindowsErrWithFilename() and
+ PyErr_SetFromWindowsErr(), but they allow to specify
+ the exception type to raise. Available on Windows.
+
+- Py_FatalError() is now declared as taking a const char* argument. It
+ was previously declared without const. This should not affect working
+ code.
+
+- Added new macro PySequence_ITEM(o, i) that directly calls
+ sq_item without rechecking that o is a sequence and without
+ adjusting for negative indices.
+
+- PyRange_New() now raises ValueError if the fourth argument is not 1.
+ This is part of the removal of deprecated features of the xrange
+ object.
+
+- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
+ coercion if both arguments have the same type but this type has the
+ CHECKTYPES flag set. This is to better support proxies.
+
+- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
+ "``void (*)(void *)``".
+
+- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
+
+- A type can now inherit its metatype from its base type. Previously,
+ when PyType_Ready() was called, if ob_type was found to be NULL, it
+ was always set to &PyType_Type; now it is set to base->ob_type,
+ where base is tp_base, defaulting to &PyObject_Type.
+
+- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
+
+- The PyCore_* family of APIs have been removed.
+
+- The "u#" parser marker will now pass through Unicode objects as-is
+ without going through the buffer API.
+
+- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
+
+- An old #define of ANY as void has been removed from pyport.h. This
+ hasn't been used since Python's pre-ANSI days, and the #define has
+ been marked as obsolete since then. SF bug 495548 says it created
+ conflicts with other packages, so keeping it around wasn't harmless.
+
+- Because Python's magic number scheme broke on January 1st, we decided
+ to stop Python development. Thanks for all the fish!
+
+- Some of us don't like fish, so we changed Python's magic number
+ scheme to a new one. See Python/import.c for details.
+
+New platforms
+-------------
+
+- OpenVMS is now supported.
+
+- AtheOS is now supported.
+
+- the EMX runtime environment on OS/2 is now supported.
+
+- GNU/Hurd is now supported.
+
+Tests
+-----
+
+- The regrtest.py script's -u option now provides a way to say "allow
+ all resources except this one." For example, to allow everything
+ except bsddb, give the option '-uall,-bsddb'.
+
+Windows
+-------
+
+- The Windows distribution now ships with version 4.0.14 of the
+ Sleepycat Berkeley database library. This should be a huge
+ improvement over the previous Berkeley DB 1.85, which had many
+ bugs.
+ XXX What are the licensing issues here?
+ XXX If a user has a database created with a previous version of
+ XXX Python, what must they do to convert it?
+ XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
+ XXX The version # is likely to change before 2.3a1.
+
+- The Windows distribution now ships with a Secure Sockets Library (SLL)
+ module (_ssl.pyd)
+
+- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
+ previously shipped with Tcl/Tk 8.3.2).
+
+- When Python is built under a Microsoft compiler, sys.version now
+ includes the compiler version number (_MSC_VER). For example, under
+ MSVC 6, sys.version contains the substring "MSC v.1200 ". 1200 is
+ the value of _MSC_VER under MSVC 6.
+
+- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
+ of that has been fixed in the installer (disabled Wise's "delete in-
+ use files" uninstall option).
+
+- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
+
+- The installer now installs Start menu shortcuts under (the local
+ equivalent of) "All Users" when doing an Admin install.
+
+- file.truncate([newsize]) now works on Windows for all newsize values.
+ It used to fail if newsize didn't fit in 32 bits, reflecting a
+ limitation of MS _chsize (which is no longer used).
+
+- os.waitpid() is now implemented for Windows, and can be used to block
+ until a specified process exits. This is similar to, but not exactly
+ the same as, os.waitpid() on POSIX systems. If you're waiting for
+ a specific process whose pid was obtained from one of the spawn()
+ functions, the same Python os.waitpid() code works across platforms.
+ See the docs for details. The docs were changed to clarify that
+ spawn functions return, and waitpid requires, a process handle on
+ Windows (not the same thing as a Windows process id).
+
+- New tempfile.TemporaryFile implementation for Windows: this doesn't
+ need a TemporaryFileWrapper wrapper anymore, and should be immune
+ to a nasty problem: before 2.3, if you got a temp file on Windows, it
+ got wrapped in an object whose close() method first closed the
+ underlying file, then deleted the file. This usually worked fine.
+ However, the spawn family of functions on Windows create (at a low C
+ level) the same set of open files in the spawned process Q as were
+ open in the spawning process P. If a temp file f was among them, then
+ doing f.close() in P first closed P's C-level file handle on f, but Q's
+ C-level file handle on f remained open, so the attempt in P to delete f
+ blew up with a "Permission denied" error (Windows doesn't allow
+ deleting open files). This was surprising, subtle, and difficult to
+ work around.
+
+- The os module now exports all the symbolic constants usable with the
+ low-level os.open() on Windows: the new constants in 2.3 are
+ O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
+ The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
+ O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
+ to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
+ (so specify both if you want both; note that neither is useful unless
+ specified with O_CREAT too).
+
+Mac
+----
+
+- Mac/Relnotes is gone, the release notes are now here.
+
+- Python (the OSX-only, unix-based version, not the OS9-compatible CFM
+ version) now fully supports unicode strings as arguments to various file
+ system calls, eg. open(), file(), os.stat() and os.listdir().
+
+- The current naming convention for Python on the Macintosh is that MacPython
+ refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
+ CFM-based version that runs on both OS9 and OSX.
+
+- All MacPython-OS9 functionality is now available in an OSX unix build,
+ including the Carbon modules, the IDE, OSA support, etc. A lot of this
+ will only work correctly in a framework build, though, because you cannot
+ talk to the window manager unless your application is run from a .app
+ bundle. There is a command line tool "pythonw" that runs your script
+ with an interpreter living in such a .app bundle, this interpreter should
+ be used to run any Python script using the window manager (including
+ Tkinter or wxPython scripts).
+
+- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
+ MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
+ are specifically for MacPython-OS9 (CFM support, preference resources, etc).
+
+- A new utility PythonLauncher will start a Python interpreter when a .py or
+ .pyw script is double-clicked in the Finder. By default .py scripts are
+ run with a normal Python interpreter in a Terminal window and .pyw
+ files are run with a window-aware pythonw interpreter without a Terminal
+ window, but all this can be customized.
+
+- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
+ possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
+ releases.
+
+- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
+ line interface too.
+
+- All the Carbon classes are now PEP253 compliant, meaning that you can
+ subclass them from Python. Most of the attributes have gone, you should
+ now use the accessor function call API, which is also what Apple's
+ documentation uses. Some attributes such as grafport.visRgn are still
+ available for convenience.
+
+- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
+ and Folder (APIs from Folders.h). The old macfs builtin module is
+ gone, and replaced by a Python wrapper around the new modules.
+
+- Pathname handling should now be fully consistent: MacPython-OSX always uses
+ unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
+ (also when running on Mac OS X).
+
+- New Carbon modules Help and AH give access to the Carbon Help Manager.
+ There are hooks in the IDE to allow accessing the Python documentation
+ (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
+ See Mac/OSX/README for converting the Python documentation to a
+ Help Viewer compatible form and installing it.
+
+- OSA support has been redesigned and the generated Python classes now
+ mirror the inheritance defined by the underlying OSA classes.
+
+- MacPython no longer maps both \r and \n to \n on input for any text file.
+ This feature has been replaced by universal newline support (PEP278).
+
+- The default encoding for Python sourcefiles in MacPython-OS9 is no longer
+ mac-roman (or whatever your local Mac encoding was) but "ascii", like on
+ other platforms. If you really need sourcefiles with Mac characters in them
+ you can change this in site.py.
+
+
+What's New in Python 2.2 final?
+===============================
+
+*Release date: 21-Dec-2001*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- pickle.py, cPickle: allow pickling instances of new-style classes
+ with a custom metaclass.
+
+Core and builtins
+-----------------
+
+- weakref proxy object: when comparing, unwrap both arguments if both
+ are proxies.
+
+Extension modules
+-----------------
+
+- binascii.b2a_base64(): fix a potential buffer overrun when encoding
+ very short strings.
+
+- cPickle: the obscure "fast" mode was suspected of causing stack
+ overflows on the Mac. Hopefully fixed this by setting the recursion
+ limit much smaller. If the limit is too low (it only affects
+ performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
+ when compiling cPickle.c (or in pyconfig.h).
+
+Library
+-------
+
+- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
+ close or delete time).
+
+- rfc822.py: fixed a bug where the address '<>' was converted to None
+ instead of an empty string (also fixes the email.Utils module).
+
+- xmlrpclib.py: version 1.0.0; uses precision for doubles.
+
+- test suite: the pickle and cPickle tests were not executing any code
+ when run from the standard regression test.
+
+Tools/Demos
+-----------
+
+Build
+-----
+
+C API
+-----
+
+New platforms
+-------------
+
+Tests
+-----
+
+Windows
+-------
+
+- distutils package: fixed broken Windows installers (bdist_wininst).
+
+- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
+ instances are deleted at process exit time.
+
+- socket.py: prevent mysterious warnings when socket instances are
+ deleted at process exit time.
+
+- posixmodule.c: fix a Windows crash with stat() of a filename ending
+ in backslash.
+
+Mac
+----
+
+- The Carbon toolbox modules have been upgraded to Universal Headers
+ 3.4, and experimental CoreGraphics and CarbonEvents modules have
+ been added. All only for framework-enabled MacOSX.
+
+
+What's New in Python 2.2c1?
+===========================
+
+*Release date: 14-Dec-2001*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- Guido's tutorial introduction to the new type/class features has
+ been extensively updated. See
+
+ http://www.python.org/2.2/descrintro.html
+
+ That remains the primary documentation in this area.
+
+- Fixed a leak: instance variables declared with __slots__ were never
+ deleted!
+
+- The "delete attribute" method of descriptor objects is called
+ __delete__, not __del__. In previous releases, it was mistakenly
+ called __del__, which created an unfortunate overloading condition
+ with finalizers. (The "get attribute" and "set attribute" methods
+ are still called __get__ and __set__, respectively.)
+
+- Some subtle issues with the super built-in were fixed:
+
+ (a) When super itself is subclassed, its __get__ method would still
+ return an instance of the base class (i.e., of super).
+
+ (b) super(C, C()).__class__ would return C rather than super. This
+ is confusing. To fix this, I decided to change the semantics of
+ super so that it only applies to code attributes, not to data
+ attributes. After all, overriding data attributes is not
+ supported anyway.
+
+ (c) The __get__ method didn't check whether the argument was an
+ instance of the type used in creation of the super instance.
+
+- Previously, hash() of an instance of a subclass of a mutable type
+ (list or dictionary) would return some value, rather than raising
+ TypeError. This has been fixed. Also, directly calling
+ dict.__hash__ and list.__hash__ now raises the same TypeError
+ (previously, these were the same as object.__hash__).
+
+- New-style objects now support deleting their __dict__. This is for
+ all intents and purposes equivalent to assigning a brand new empty
+ dictionary, but saves space if the object is not used further.
+
+Core and builtins
+-----------------
+
+- -Qnew now works as documented in PEP 238: when -Qnew is passed on
+ the command line, all occurrences of "/" use true division instead
+ of classic division. See the PEP for details. Note that "all"
+ means all instances in library and 3rd-party modules, as well as in
+ your own code. As the PEP says, -Qnew is intended for use only in
+ educational environments with control over the libraries in use.
+ Note that test_coercion.py in the standard Python test suite fails
+ under -Qnew; this is expected, and won't be repaired until true
+ division becomes the default (in the meantime, test_coercion is
+ testing the current rules).
+
+- complex() now only allows the first argument to be a string
+ argument, and raises TypeError if either the second arg is a string
+ or if the second arg is specified when the first is a string.
+
+Extension modules
+-----------------
+
+- gc.get_referents was renamed to gc.get_referrers.
+
+Library
+-------
+
+- Functions in the os.spawn() family now release the global interpreter
+ lock around calling the platform spawn. They should always have done
+ this, but did not before 2.2c1. Multithreaded programs calling
+ an os.spawn function with P_WAIT will no longer block all Python threads
+ until the spawned program completes. It's possible that some programs
+ relies on blocking, although more likely by accident than by design.
+
+- webbrowser defaults to netscape.exe on OS/2 now.
+
+- Tix.ResizeHandle exposes detach_widget, hide, and show.
+
+- The charset alias windows_1252 has been added.
+
+- types.StringTypes is a tuple containing the defined string types;
+ usually this will be (str, unicode), but if Python was compiled
+ without Unicode support it will be just (str,).
+
+- The pulldom and minidom modules were synchronized to PyXML.
+
+Tools/Demos
+-----------
+
+- A new script called Tools/scripts/google.py was added, which fires
+ off a search on Google.
+
+Build
+-----
+
+- Note that release builds of Python should arrange to define the
+ preprocessor symbol NDEBUG on the command line (or equivalent).
+ In the 2.2 pre-release series we tried to define this by magic in
+ Python.h instead, but it proved to cause problems for extension
+ authors. The Unix, Windows and Mac builds now all define NDEBUG in
+ release builds via cmdline (or equivalent) instead. Ports to
+ other platforms should do likewise.
+
+- It is no longer necessary to use --with-suffix when building on a
+ case-insensitive file system (such as Mac OS X HFS+). In the build
+ directory an extension is used, but not in the installed python.
+
+C API
+-----
+
+- New function PyDict_MergeFromSeq2() exposes the builtin dict
+ constructor's logic for updating a dictionary from an iterable object
+ producing key-value pairs.
+
+- PyArg_ParseTupleAndKeywords() requires that the number of entries in
+ the keyword list equal the number of argument specifiers. This
+ wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
+ dump core in some bad cases. This has been repaired. As a result,
+ PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
+ previously went unchallenged.
+
+New platforms
+-------------
+
+Tests
+-----
+
+Windows
+-------
+
+Mac
+----
+
+- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
+ without any trailing digits.
+
+- Changed logic for finding python home in Mac OS X framework Pythons.
+ Now sys.executable points to the executable again, in stead of to
+ the shared library. The latter is used only for locating the python
+ home.
+
+
+What's New in Python 2.2b2?
+===========================
+
+*Release date: 16-Nov-2001*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- Multiple inheritance mixing new-style and classic classes in the
+ list of base classes is now allowed, so this works now:
+
+ class Classic: pass
+ class Mixed(Classic, object): pass
+
+ The MRO (method resolution order) for each base class is respected
+ according to its kind, but the MRO for the derived class is computed
+ using new-style MRO rules if any base class is a new-style class.
+ This needs to be documented.
+
+- The new builtin dictionary() constructor, and dictionary type, have
+ been renamed to dict. This reflects a decade of common usage.
+
+- dict() now accepts an iterable object producing 2-sequences. For
+ example, dict(d.items()) == d for any dictionary d. The argument,
+ and the elements of the argument, can be any iterable objects.
+
+- New-style classes can now have a __del__ method, which is called
+ when the instance is deleted (just like for classic classes).
+
+- Assignment to object.__dict__ is now possible, for objects that are
+ instances of new-style classes that have a __dict__ (unless the base
+ class forbids it).
+
+- Methods of built-in types now properly check for keyword arguments
+ (formerly these were silently ignored). The only built-in methods
+ that take keyword arguments are __call__, __init__ and __new__.
+
+- The socket function has been converted to a type; see below.
+
+Core and builtins
+-----------------
+
+- Assignment to __debug__ raises SyntaxError at compile-time. This
+ was promised when 2.1c1 was released as "What's New in Python 2.1c1"
+ (see below) says.
+
+- Clarified the error messages for unsupported operands to an operator
+ (like 1 + '').
+
+Extension modules
+-----------------
+
+- mmap has a new keyword argument, "access", allowing a uniform way for
+ both Windows and Unix users to create read-only, write-through and
+ copy-on-write memory mappings. This was previously possible only on
+ Unix. A new keyword argument was required to support this in a
+ uniform way because the mmap() signatures had diverged across
+ platforms. Thanks to Jay T Miller for repairing this!
+
+- By default, the gc.garbage list now contains only those instances in
+ unreachable cycles that have __del__ methods; in 2.1 it contained all
+ instances in unreachable cycles. "Instances" here has been generalized
+ to include instances of both new-style and old-style classes.
+
+- The socket module defines a new method for socket objects,
+ sendall(). This is like send() but may make multiple calls to
+ send() until all data has been sent. Also, the socket function has
+ been converted to a subclassable type, like list and tuple (etc.)
+ before it; socket and SocketType are now the same thing.
+
+- Various bugfixes to the curses module. There is now a test suite
+ for the curses module (you have to run it manually).
+
+- binascii.b2a_base64 no longer places an arbitrary restriction of 57
+ bytes on its input.
+
+Library
+-------
+
+- tkFileDialog exposes a Directory class and askdirectory
+ convenience function.
+
+- Symbolic group names in regular expressions must be unique. For
+ example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
+ single name can't mean both "group 1" and "group 2" simultaneously.
+ Python 2.2 detects this error at regexp compilation time;
+ previously, the error went undetected, and results were
+ unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
+ pattern.subn() methods have been rewritten in C. Also, an
+ experimental function/method finditer() has been added, which works
+ like findall() but returns an iterator.
+
+- Tix exposes more commands through the classes DirSelectBox,
+ DirSelectDialog, ListNoteBook, Meter, CheckList, and the
+ methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
+ tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
+
+- Traceback objects are now scanned by cyclic garbage collection, so
+ cycles created by casual use of sys.exc_info() no longer cause
+ permanent memory leaks (provided garbage collection is enabled).
+
+- os.extsep -- a new variable needed by the RISCOS support. It is the
+ separator used by extensions, and is '.' on all platforms except
+ RISCOS, where it is '/'. There is no need to use this variable
+ unless you have a masochistic desire to port your code to RISCOS.
+
+- mimetypes.py has optional support for non-standard, but commonly
+ found types. guess_type() and guess_extension() now accept an
+ optional 'strict' flag, defaulting to true, which controls whether
+ recognize non-standard types or not. A few non-standard types we
+ know about have been added. Also, when run as a script, there are
+ new -l and -e options.
+
+- statcache is now deprecated.
+
+- email.Utils.formatdate() now produces the preferred RFC 2822 style
+ dates with numeric timezones (it used to produce obsolete dates
+ hard coded to "GMT" timezone). An optional 'localtime' flag is
+ added to produce dates in the local timezone, with daylight savings
+ time properly taken into account.
+
+- In pickle and cPickle, instead of masking errors in load() by
+ transforming them into SystemError, we let the original exception
+ propagate out. Also, implement support for __safe_for_unpickling__
+ in pickle, as it already was supported in cPickle.
+
+Tools/Demos
+-----------
+
+Build
+-----
+
+- The dbm module is built using libdb1 if available. The bsddb module
+ is built with libdb3 if available.
+
+- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
+
+C API
+-----
+
+- New function PySequence_Fast_GET_SIZE() returns the size of a non-
+ NULL result from PySequence_Fast(), more quickly than calling
+ PySequence_Size().
+
+- New argument unpacking function PyArg_UnpackTuple() added.
+
+- New functions PyObject_CallFunctionObjArgs() and
+ PyObject_CallMethodObjArgs() have been added to make it more
+ convenient and efficient to call functions and methods from C.
+
+- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
+ possible that this will propagate errors it didn't before.
+
+- New function PyObject_CheckReadBuffer(), which returns true if its
+ argument supports the single-segment readable buffer interface.
+
+New platforms
+-------------
+
+- We've finally confirmed that this release builds on HP-UX 11.00,
+ *with* threads, and passes the test suite.
+
+- Thanks to a series of patches from Michael Muller, Python may build
+ again under OS/2 Visual Age C++.
+
+- Updated RISCOS port by Dietmar Schwertberger.
+
+Tests
+-----
+
+- Added a test script for the curses module. It isn't run automatically;
+ regrtest.py must be run with '-u curses' to enable it.
+
+Windows
+-------
+
+Mac
+----
+
+- PythonScript has been moved to unsupported and is slated to be
+ removed completely in the next release.
+
+- It should now be possible to build applets that work on both OS9 and
+ OSX.
+
+- The core is now linked with CoreServices not Carbon; as a side
+ result, default 8bit encoding on OSX is now ASCII.
+
+- Python should now build on OSX 10.1.1
+
+
+What's New in Python 2.2b1?
+===========================
+
+*Release date: 19-Oct-2001*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- New-style classes are now always dynamic (except for built-in and
+ extension types). There is no longer a performance penalty, and I
+ no longer see another reason to keep this baggage around. One relic
+ remains: the __dict__ of a new-style class is a read-only proxy; you
+ must set the class's attribute to modify it. As a consequence, the
+ __defined__ attribute of new-style types no longer exists, for lack
+ of need: there is once again only one __dict__ (although in the
+ future a __cache__ may be resurrected with a similar function, if I
+ can prove that it actually speeds things up).
+
+- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
+ always returned None, even when there was a class docstring).
+
+- doctest now finds and runs docstrings attached to new-style classes,
+ class methods, static methods, and properties.
+
+Core and builtins
+-----------------
+
+- A very subtle syntactical pitfall in list comprehensions was fixed.
+ For example: [a+b for a in 'abc', for b in 'def']. The comma in
+ this example is a mistake. Previously, this would silently let 'a'
+ iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
+ 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
+ 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
+ Note that [a for a in <singleton>] is a convoluted way to say
+ [<singleton>] anyway, so it's not like any expressiveness is lost.
+
+- getattr(obj, name, default) now only catches AttributeError, as
+ documented, rather than returning the default value for all
+ exceptions (which could mask bugs in a __getattr__ hook, for
+ example).
+
+- Weak reference objects are now part of the core and offer a C API.
+ A bug which could allow a core dump when binary operations involved
+ proxy reference has been fixed. weakref.ReferenceError is now a
+ built-in exception.
+
+- unicode(obj) now behaves more like str(obj), accepting arbitrary
+ objects, and calling a __unicode__ method if it exists.
+ unicode(obj, encoding) and unicode(obj, encoding, errors) still
+ require an 8-bit string or character buffer argument.
+
+- isinstance() now allows any object as the first argument and a
+ class, a type or something with a __bases__ tuple attribute for the
+ second argument. The second argument may also be a tuple of a
+ class, type, or something with __bases__, in which case isinstance()
+ will return true if the first argument is an instance of any of the
+ things contained in the second argument tuple. E.g.
+
+ isinstance(x, (A, B))
+
+ returns true if x is an instance of A or B.
+
+Extension modules
+-----------------
+
+- thread.start_new_thread() now returns the thread ID (previously None).
+
+- binascii has now two quopri support functions, a2b_qp and b2a_qp.
+
+- readline now supports setting the startup_hook and the
+ pre_event_hook, and adds the add_history() function.
+
+- os and posix supports chroot(), setgroups() and unsetenv() where
+ available. The stat(), fstat(), statvfs() and fstatvfs() functions
+ now return "pseudo-sequences" -- the various fields can now be
+ accessed as attributes (e.g. os.stat("/").st_mtime) but for
+ backwards compatibility they also behave as a fixed-length sequence.
+ Some platform-specific fields (e.g. st_rdev) are only accessible as
+ attributes.
+
+- time: localtime(), gmtime() and strptime() now return a
+ pseudo-sequence similar to the os.stat() return value, with
+ attributes like tm_year etc.
+
+- Decompression objects in the zlib module now accept an optional
+ second parameter to decompress() that specifies the maximum amount
+ of memory to use for the uncompressed data.
+
+- optional SSL support in the socket module now exports OpenSSL
+ functions RAND_add(), RAND_egd(), and RAND_status(). These calls
+ are useful on platforms like Solaris where OpenSSL does not
+ automatically seed its PRNG. Also, the keyfile and certfile
+ arguments to socket.ssl() are now optional.
+
+- posixmodule (and by extension, the os module on POSIX platforms) now
+ exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
+
+Library
+-------
+
+- doctest now excludes functions and classes not defined by the module
+ being tested, thanks to Tim Hochberg.
+
+- HotShot, a new profiler implemented using a C-based callback, has
+ been added. This substantially reduces the overhead of profiling,
+ but it is still quite preliminary. Support modules and
+ documentation will be added in upcoming releases (before 2.2 final).
+
+- profile now produces correct output in situations where an exception
+ raised in Python is cleared by C code (e.g. hasattr()). This used
+ to cause wrong output, including spurious claims of recursive
+ functions and attribution of time spent to the wrong function.
+
+ The code and documentation for the derived OldProfile and HotProfile
+ profiling classes was removed. The code hasn't worked for years (if
+ you tried to use them, they raised exceptions). OldProfile
+ intended to reproduce the behavior of the profiler Python used more
+ than 7 years ago, and isn't interesting anymore. HotProfile intended
+ to provide a faster profiler (but producing less information), and
+ that's a worthy goal we intend to meet via a different approach (but
+ without losing information).
+
+- Profile.calibrate() has a new implementation that should deliver
+ a much better system-specific calibration constant. The constant can
+ now be specified in an instance constructor, or as a Profile class or
+ instance variable, instead of by editing profile.py's source code.
+ Calibration must still be done manually (see the docs for the profile
+ module).
+
+ Note that Profile.calibrate() must be overridden by subclasses.
+ Improving the accuracy required exploiting detailed knowledge of
+ profiler internals; the earlier method abstracted away the details
+ and measured a simplified model instead, but consequently computed
+ a constant too small by a factor of 2 on some modern machines.
+
+- quopri's encode and decode methods take an optional header parameter,
+ which indicates whether output is intended for the header 'Q'
+ encoding.
+
+- The SocketServer.ThreadingMixIn class now closes the request after
+ finish_request() returns. (Not when it errors out though.)
+
+- The nntplib module's NNTP.body() method has grown a 'file' argument
+ to allow saving the message body to a file.
+
+- The email package has added a class email.Parser.HeaderParser which
+ only parses headers and does not recurse into the message's body.
+ Also, the module/class MIMEAudio has been added for representing
+ audio data (contributed by Anthony Baxter).
+
+- ftplib should be able to handle files > 2GB.
+
+- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
+ ON, and OFF.
+
+- xml.dom.minidom NodeList objects now support the length attribute
+ and item() method as required by the DOM specifications.
+
+Tools/Demos
+-----------
+
+- Demo/dns was removed. It no longer serves any purpose; a package
+ derived from it is now maintained by Anthony Baxter, see
+ http://PyDNS.SourceForge.net.
+
+- The freeze tool has been made more robust, and two new options have
+ been added: -X and -E.
+
+Build
+-----
+
+- configure will use CXX in LINKCC if CXX is used to build main() and
+ the system requires to link a C++ main using the C++ compiler.
+
+C API
+-----
+
+- The documentation for the tp_compare slot is updated to require that
+ the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
+ not correct. This is not yet enforced but will be enforced in
+ Python 2.3; even later, we may use -2 to indicate errors and +2 for
+ "NotImplemented". Right now, -1 should be used for an error return.
+
+- PyLong_AsLongLong() now accepts int (as well as long) arguments.
+ Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
+ as long) arguments.
+
+- PyThread_start_new_thread() now returns a long int giving the thread
+ ID, if one can be calculated; it returns -1 for error, 0 if no
+ thread ID is calculated (this is an incompatible change, but only
+ the thread module used this API). This code has only really been
+ tested on Linux and Windows; other platforms please beware (and
+ report any bugs or strange behavior).
+
+- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
+ input.
+
+New platforms
+-------------
+
+Tests
+-----
+
+Windows
+-------
+
+- Installer: If you install IDLE, and don't disable file-extension
+ registration, a new "Edit with IDLE" context (right-click) menu entry
+ is created for .py and .pyw files.
+
+- The signal module now supports SIGBREAK on Windows, thanks to Steven
+ Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
+ action remains to call Win32 ExitProcess(). This can be changed via
+ signal.signal(). For example::
+
+ # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
+ # (SIGINT) behavior.
+ import signal
+ signal.signal(signal.SIGBREAK, signal.default_int_handler)
+
+ try:
+ while 1:
+ pass
+ except KeyboardInterrupt:
+ # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
+ # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
+ # program without the possibility for any Python-level cleanup).
+ print "Clean exit"
+
+
+What's New in Python 2.2a4?
+===========================
+
+*Release date: 28-Sep-2001*
+
+Type/class unification and new-style classes
+--------------------------------------------
+
+- pydoc and inspect are now aware of new-style classes;
+ e.g. help(list) at the interactive prompt now shows proper
+ documentation for all operations on list objects.
+
+- Applications using Jim Fulton's ExtensionClass module can now safely
+ be used with Python 2.2. In particular, Zope 2.4.1 now works with
+ Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
+ examples also work again. It is hoped that Gtk and Boost also work
+ with 2.2a4 and beyond. (If you can confirm this, please write
+ webmaster at python.org; if there are still problems, please open a bug
+ report on SourceForge.)
+
+- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
+ These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
+ in the constructed property object. fget, fset and fdel weren't
+ discoverable from Python in 2.2a3. __doc__ is new, and allows to
+ associate a docstring with a property.
+
+- Comparison overloading is now more completely implemented. For
+ example, a str subclass instance can properly be compared to a str
+ instance, and it can properly overload comparison. Ditto for most
+ other built-in object types.
+
+- The repr() of new-style classes has changed; instead of <type
+ 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
+ *except* for built-in types, which are still rendered as <type
+ 'Foo'> (to avoid upsetting existing code that might parse or
+ otherwise rely on repr() of certain type objects).
+
+- The repr() of new-style objects is now always <Foo object at XXX>;
+ previously, it was sometimes <Foo instance at XXX>.
+
+- For new-style classes, what was previously called __getattr__ is now
+ called __getattribute__. This method, if defined, is called for
+ *every* attribute access. A new __getattr__ hook more similar to the
+ one in classic classes is defined which is called only if regular
+ attribute access raises AttributeError; to catch *all* attribute
+ access, you can use __getattribute__ (for new-style classes). If
+ both are defined, __getattribute__ is called first, and if it raises
+ AttributeError, __getattr__ is called.
+
+- The __class__ attribute of new-style objects can be assigned to.
+ The new class must have the same C-level object layout as the old
+ class.
+
+- The builtin file type can be subclassed now. In the usual pattern,
+ "file" is the name of the builtin type, and file() is a new builtin
+ constructor, with the same signature as the builtin open() function.
+ file() is now the preferred way to open a file.
+
+- Previously, __new__ would only see sequential arguments passed to
+ the type in a constructor call; __init__ would see both sequential
+ and keyword arguments. This made no sense whatsoever any more, so
+ now both __new__ and __init__ see all arguments.
+
+- Previously, hash() applied to an instance of a subclass of str or
+ unicode always returned 0. This has been repaired.
+
+- Previously, an operation on an instance of a subclass of an
+ immutable type (int, long, float, complex, tuple, str, unicode),
+ where the subtype didn't override the operation (and so the
+ operation was handled by the builtin type), could return that
+ instance instead a value of the base type. For example, if s was of
+ a str subclass type, s[:] returned s as-is. Now it returns a str
+ with the same value as s.
+
+- Provisional support for pickling new-style objects has been added.
+
+Core
+----
+
+- file.writelines() now accepts any iterable object producing strings.
+
+- PyUnicode_FromEncodedObject() now works very much like
+ PyObject_Str(obj) in that it tries to use __str__/tp_str
+ on the object if the object is not a string or buffer. This
+ makes unicode() behave like str() when applied to non-string/buffer
+ objects.
+
+- PyFile_WriteObject now passes Unicode objects to the file's write
+ method. As a result, all file-like objects which may be the target
+ of a print statement must support Unicode objects, i.e. they must
+ at least convert them into ASCII strings.
+
+- Thread scheduling on Solaris should be improved; it is no longer
+ necessary to insert a small sleep at the start of a thread in order
+ to let other runnable threads be scheduled.
+
+Library
+-------
+
+- StringIO.StringIO instances and cStringIO.StringIO instances support
+ read character buffer compatible objects for their .write() methods.
+ These objects are converted to strings and then handled as such
+ by the instances.
+
+- The "email" package has been added. This is basically a port of the
+ mimelib package <http://sf.net/projects/mimelib> with API changes
+ and some implementations updated to use iterators and generators.
+
+- difflib.ndiff() and difflib.Differ.compare() are generators now. This
+ restores the ability of Tools/scripts/ndiff.py to start producing output
+ before the entire comparison is complete.
+
+- StringIO.StringIO instances and cStringIO.StringIO instances support
+ iteration just like file objects (i.e. their .readline() method is
+ called for each iteration until it returns an empty string).
+
+- The codecs module has grown four new helper APIs to access
+ builtin codecs: getencoder(), getdecoder(), getreader(),
+ getwriter().
+
+- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
+ simplifies writing XML RPC servers.
+
+- os.path.realpath(): a new function that returns the absolute pathname
+ after interpretation of symbolic links. On non-Unix systems, this
+ is an alias for os.path.abspath().
+
+- operator.indexOf() (PySequence_Index() in the C API) now works with any
+ iterable object.
+
+- smtplib now supports various authentication and security features of
+ the SMTP protocol through the new login() and starttls() methods.
+
+- hmac: a new module implementing keyed hashing for message
+ authentication.
+
+- mimetypes now recognizes more extensions and file types. At the
+ same time, some mappings not sanctioned by IANA were removed.
+
+- The "compiler" package has been brought up to date to the state of
+ Python 2.2 bytecode generation. It has also been promoted from a
+ Tool to a standard library package. (Tools/compiler still exists as
+ a sample driver.)
+
+Build
+-----
+
+- Large file support (LFS) is now automatic when the platform supports
+ it; no more manual configuration tweaks are needed. On Linux, at
+ least, it's possible to have a system whose C library supports large
+ files but whose kernel doesn't; in this case, large file support is
+ still enabled but doesn't do you any good unless you upgrade your
+ kernel or share your Python executable with another system whose
+ kernel has large file support.
+
+- The configure script now supplies plausible defaults in a
+ cross-compilation environment. This doesn't mean that the supplied
+ values are always correct, or that cross-compilation now works
+ flawlessly -- but it's a first step (and it shuts up most of
+ autoconf's warnings about AC_TRY_RUN).
+
+- The Unix build is now a bit less chatty, courtesy of the parser
+ generator. The build is completely silent (except for errors) when
+ using "make -s", thanks to a -q option to setup.py.
+
+C API
+-----
+
+- The "structmember" API now supports some new flag bits to deny read
+ and/or write access to attributes in restricted execution mode.
+
+New platforms
+-------------
+
+- Compaq's iPAQ handheld, running the "familiar" Linux distribution
+ (http://familiar.handhelds.org).
+
+Tests
+-----
+
+- The "classic" standard tests, which work by comparing stdout to
+ an expected-output file under Lib/test/output/, no longer stop at
+ the first mismatch. Instead the test is run to completion, and a
+ variant of ndiff-style comparison is used to report all differences.
+ This is much easier to understand than the previous style of reporting.
+
+- The unittest-based standard tests now use regrtest's test_main()
+ convention, instead of running as a side-effect of merely being
+ imported. This allows these tests to be run in more natural and
+ flexible ways as unittests, outside the regrtest framework.
+
+- regrtest.py is much better integrated with unittest and doctest now,
+ especially in regard to reporting errors.
+
+Windows
+-------
+
+- Large file support now also works for files > 4GB, on filesystems
+ that support it (NTFS under Windows 2000). See "What's New in
+ Python 2.2a3" for more detail.
+
+
+What's New in Python 2.2a3?
+===========================
+
+*Release Date: 07-Sep-2001*
+
+Core
+----
+
+- Conversion of long to float now raises OverflowError if the long is too
+ big to represent as a C double.
+
+- The 3-argument builtin pow() no longer allows a third non-None argument
+ if either of the first two arguments is a float, or if both are of
+ integer types and the second argument is negative (in which latter case
+ the arguments are converted to float, so this is really the same
+ restriction).
+
+- The builtin dir() now returns more information, and sometimes much
+ more, generally naming all attributes of an object, and all attributes
+ reachable from the object via its class, and from its class's base
+ classes, and so on from them too. Example: in 2.2a2, dir([]) returned
+ an empty list. In 2.2a3,
+
+ >>> dir([])
+ ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
+ '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
+ '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
+ '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
+ '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
+ 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
+ 'reverse', 'sort']
+
+ dir(module) continues to return only the module's attributes, though.
+
+- Overflowing operations on plain ints now return a long int rather
+ than raising OverflowError. This is a partial implementation of PEP
+ 237. You can use -Wdefault::OverflowWarning to enable a warning for
+ this situation, and -Werror::OverflowWarning to revert to the old
+ OverflowError exception.
+
+- A new command line option, -Q<arg>, is added to control run-time
+ warnings for the use of classic division. (See PEP 238.) Possible
+ values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
+ -Qold, meaning the / operator has its classic meaning and no
+ warnings are issued. Using -Qwarn issues a run-time warning about
+ all uses of classic division for int and long arguments; -Qwarnall
+ also warns about classic division for float and complex arguments
+ (for use with fixdiv.py).
+ [Note: the remainder of this item (preserved below) became
+ obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
+
+ Using -Qnew is questionable; it turns on new division by default, but
+ only in the __main__ module. You can usefully combine -Qwarn or
+ -Qwarnall and -Qnew: this gives the __main__ module new division, and
+ warns about classic division everywhere else.
+
+- Many built-in types can now be subclassed. This applies to int,
+ long, float, str, unicode, and tuple. (The types complex, list and
+ dictionary can also be subclassed; this was introduced earlier.)
+ Note that restrictions apply when subclassing immutable built-in
+ types: you can only affect the value of the instance by overloading
+ __new__. You can add mutable attributes, and the subclass instances
+ will have a __dict__ attribute, but you cannot change the "value"
+ (as implemented by the base class) of an immutable subclass instance
+ once it is created.
+
+- The dictionary constructor now takes an optional argument, a
+ mapping-like object, and initializes the dictionary from its
+ (key, value) pairs.
+
+- A new built-in type, super, has been added. This facilitates making
+ "cooperative super calls" in a multiple inheritance setting. For an
+ explanation, see http://www.python.org/2.2/descrintro.html#cooperation
+
+- A new built-in type, property, has been added. This enables the
+ creation of "properties". These are attributes implemented by
+ getter and setter functions (or only one of these for read-only or
+ write-only attributes), without the need to override __getattr__.
+ See http://www.python.org/2.2/descrintro.html#property
+
+- The syntax of floating-point and imaginary literals has been
+ liberalized, to allow leading zeroes. Examples of literals now
+ legal that were SyntaxErrors before:
+
+ 00.0 0e3 0100j 07.5 00000000000000000008.
+
+- An old tokenizer bug allowed floating point literals with an incomplete
+ exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
+
+Library
+-------
+
+- telnetlib includes symbolic names for the options, and support for
+ setting an option negotiation callback. It also supports processing
+ of suboptions.
+
+- The new C standard no longer requires that math libraries set errno to
+ ERANGE on overflow. For platform libraries that exploit this new
+ freedom, Python's overflow-checking was wholly broken. A new overflow-
+ checking scheme attempts to repair that, but may not be reliable on all
+ platforms (C doesn't seem to provide anything both useful and portable
+ in this area anymore).
+
+- Asynchronous timeout actions are available through the new class
+ threading.Timer.
+
+- math.log and math.log10 now return sensible results for even huge
+ long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
+
+- A new function, imp.lock_held(), returns 1 when the import lock is
+ currently held. See the docs for the imp module.
+
+- pickle, cPickle and marshal on 32-bit platforms can now correctly read
+ dumps containing ints written on platforms where Python ints are 8 bytes.
+ When read on a box where Python ints are 4 bytes, such values are
+ converted to Python longs.
+
+- In restricted execution mode (using the rexec module), unmarshalling
+ code objects is no longer allowed. This plugs a security hole.
+
+- unittest.TestResult instances no longer store references to tracebacks
+ generated by test failures. This prevents unexpected dangling references
+ to objects that should be garbage collected between tests.
+
+Tools
+-----
+
+- Tools/scripts/fixdiv.py has been added which can be used to fix
+ division operators as per PEP 238.
+
+Build
+-----
+
+- If you are an adventurous person using Mac OS X you may want to look at
+ Mac/OSX. There is a Makefile there that will build Python as a real Mac
+ application, which can be used for experimenting with Carbon or Cocoa.
+ Discussion of this on pythonmac-sig, please.
+
+C API
+-----
+
+- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
+
+- Note that PyLong_AsDouble can fail! This has always been true, but no
+ callers checked for it. It's more likely to fail now, because overflow
+ errors are properly detected now. The proper way to check::
+
+ double x = PyLong_AsDouble(some_long_object);
+ if (x == -1.0 && PyErr_Occurred()) {
+ /* The conversion failed. */
+ }
+
+- The GC API has been changed. Extensions that use the old API will still
+ compile but will not participate in GC. To upgrade an extension
+ module:
+
+ - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
+
+ - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
+ PyObject_GC_Del to deallocate them
+
+ - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
+ to PyObject_GC_UnTrack
+
+ - remove PyGC_HEAD_SIZE from object size calculations
+
+ - remove calls to PyObject_AS_GC and PyObject_FROM_GC
+
+- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
+ These can be used safely to construct string objects from a
+ sprintf-style format string (similar to the format string supported
+ by PyErr_Format()).
+
+New platforms
+-------------
+
+- Stephen Hansen contributed patches sufficient to get a clean compile
+ under Borland C (Windows), but he reports problems running it and ran
+ out of time to complete the port. Volunteers? Expect a MemoryError
+ when importing the types module; this is probably shallow, and
+ causing later failures too.
+
+Tests
+-----
+
+Windows
+-------
+
+- Large file support is now enabled on Win32 platforms as well as on
+ Win64. This means that, for example, you can use f.tell() and f.seek()
+ to manipulate files larger than 2 gigabytes (provided you have enough
+ disk space, and are using a Windows filesystem that supports large
+ partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
+ filesize limit, and large file support makes no difference there.
+ FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
+ NTFS has no practical limit on file size, and files of any size can be
+ used from Python now.
+
+- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
+ points to command.com (patch from Brian Quinlan).
+
+
+What's New in Python 2.2a2?
+===========================
+
+*Release Date: 22-Aug-2001*
+
+Build
+-----
+
+- Tim Peters developed a brand new Windows installer using Wise 8.1,
+ generously donated to us by Wise Solutions.
+
+- configure supports a new option --enable-unicode, with the values
+ ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
+ type and supporting code is completely removed from the interpreter.
+
+- A new configure option --enable-framework builds a Mac OS X framework,
+ which "make frameworkinstall" will install. This provides a starting
+ point for more mac-like functionality, join pythonmac-sig at python.org
+ if you are interested in helping.
+
+- The NeXT platform is no longer supported.
+
+- The 'new' module is now statically linked.
+
+Tools
+-----
+
+- The new Tools/scripts/cleanfuture.py can be used to automatically
+ edit out obsolete future statements from Python source code. See
+ the module docstring for details.
+
+Tests
+-----
+
+- regrtest.py now knows which tests are expected to be skipped on some
+ platforms, allowing to give clearer test result output. regrtest
+ also has optional --use/-u switch to run normally disabled tests
+ which require network access or consume significant disk resources.
+
+- Several new tests in the standard test suite, with special thanks to
+ Nick Mathewson.
+
+Core
+----
+
+- The floor division operator // has been added as outlined in PEP
+ 238. The / operator still provides classic division (and will until
+ Python 3.0) unless "from __future__ import division" is included, in
+ which case the / operator will provide true division. The operator
+ module provides truediv() and floordiv() functions. Augmented
+ assignment variants are included, as are the equivalent overloadable
+ methods and C API methods. See the PEP for a full discussion:
+ <http://python.sf.net/peps/pep-0238.html>
+
+- Future statements are now effective in simulated interactive shells
+ (like IDLE). This should "just work" by magic, but read Michael
+ Hudson's "Future statements in simulated shells" PEP 264 for full
+ details: <http://python.sf.net/peps/pep-0264.html>.
+
+- The type/class unification (PEP 252-253) was integrated into the
+ trunk and is not so tentative any more (the exact specification of
+ some features is still tentative). A lot of work has done on fixing
+ bugs and adding robustness and features (performance still has to
+ come a long way).
+
+- Warnings about a mismatch in the Python API during extension import
+ now use the Python warning framework (which makes it possible to
+ write filters for these warnings).
+
+- A function's __dict__ (aka func_dict) will now always be a
+ dictionary. It used to be possible to delete it or set it to None,
+ but now both actions raise TypeErrors. It is still legal to set it
+ to a dictionary object. Getting func.__dict__ before any attributes
+ have been assigned now returns an empty dictionary instead of None.
+
+- A new command line option, -E, was added which disables the use of
+ all environment variables, or at least those that are specifically
+ significant to Python. Usually those have a name starting with
+ "PYTHON". This was used to fix a problem where the tests fail if
+ the user happens to have PYTHONHOME or PYTHONPATH pointing to an
+ older distribution.
+
+Library
+-------
+
+- New class Differ and new functions ndiff() and restore() in difflib.py.
+ These package the algorithms used by the popular Tools/scripts/ndiff.py,
+ for programmatic reuse.
+
+- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
+ value using the minimal quoting required for the value; more
+ reliable than using xml.sax.saxutils.escape() for attribute values.
+
+- Readline completion support for cmd.Cmd was added.
+
+- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
+
+- Added function threading.BoundedSemaphore()
+
+- Added Ka-Ping Yee's cgitb.py module.
+
+- The 'new' module now exposes the CO_xxx flags.
+
+- The gc module offers the get_referents function.
+
+New platforms
+-------------
+
+C API
+-----
+
+- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
+ which provide a cross-platform implementations for the
+ relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
+ the standard sprintf() and vsprintf() C lib APIs, these versions
+ apply bounds checking on the used buffer which enhances protection
+ against buffer overruns.
+
+- Unicode APIs now use name mangling to assure that mixing interpreters
+ and extensions using different Unicode widths is rendered next to
+ impossible. Trying to import an incompatible Unicode-aware extension
+ will result in an ImportError. Unicode extensions writers must make
+ sure to check the Unicode width compatibility in their extensions by
+ using at least one of the mangled Unicode APIs in the extension.
+
+- Two new flags METH_NOARGS and METH_O are available in method definition
+ tables to simplify implementation of methods with no arguments and a
+ single untyped argument. Calling such methods is more efficient than
+ calling corresponding METH_VARARGS methods. METH_OLDARGS is now
+ deprecated.
+
+Windows
+-------
+
+- "import module" now compiles module.pyw if it exists and nothing else
+ relevant is found.
+
+
+What's New in Python 2.2a1?
+===========================
+
+*Release date: 18-Jul-2001*
+
+Core
+----
+
+- TENTATIVELY, a large amount of code implementing much of what's
+ described in PEP 252 (Making Types Look More Like Classes) and PEP
+ 253 (Subtyping Built-in Types) was added. This will be released
+ with Python 2.2a1. Documentation will be provided separately
+ through http://www.python.org/2.2/. The purpose of releasing this
+ with Python 2.2a1 is to test backwards compatibility. It is
+ possible, though not likely, that a decision is made not to release
+ this code as part of 2.2 final, if any serious backwards
+ incompatibilities are found during alpha testing that cannot be
+ repaired.
+
+- Generators were added; this is a new way to create an iterator (see
+ below) using what looks like a simple function containing one or
+ more 'yield' statements. See PEP 255. Since this adds a new
+ keyword to the language, this feature must be enabled by including a
+ future statement: "from __future__ import generators" (see PEP 236).
+ Generators will become a standard feature in a future release
+ (probably 2.3). Without this future statement, 'yield' remains an
+ ordinary identifier, but a warning is issued each time it is used.
+ (These warnings currently don't conform to the warnings framework of
+ PEP 230; we intend to fix this in 2.2a2.)
+
+- The UTF-16 codec was modified to be more RFC compliant. It will now
+ only remove BOM characters at the start of the string and then
+ only if running in native mode (UTF-16-LE and -BE won't remove a
+ leading BMO character).
+
+- Strings now have a new method .decode() to complement the already
+ existing .encode() method. These two methods provide direct access
+ to the corresponding decoders and encoders of the registered codecs.
+
+ To enhance the usability of the .encode() method, the special
+ casing of Unicode object return values was dropped (Unicode objects
+ were auto-magically converted to string using the default encoding).
+
+ Both methods will now return whatever the codec in charge of the
+ requested encoding returns as object, e.g. Unicode codecs will
+ return Unicode objects when decoding is requested ("äöü".decode("latin-1")
+ will return u"äöü"). This enables codec writer to create codecs
+ for various simple to use conversions.
+
+ New codecs were added to demonstrate these new features (the .encode()
+ and .decode() columns indicate the type of the returned objects):
+
+ +---------+-----------+-----------+-----------------------------+
+ |Name | .encode() | .decode() | Description |
+ +=========+===========+===========+=============================+
+ |uu | string | string | UU codec (e.g. for email) |
+ +---------+-----------+-----------+-----------------------------+
+ |base64 | string | string | base64 codec |
+ +---------+-----------+-----------+-----------------------------+
+ |quopri | string | string | quoted-printable codec |
+ +---------+-----------+-----------+-----------------------------+
+ |zlib | string | string | zlib compression |
+ +---------+-----------+-----------+-----------------------------+
+ |hex | string | string | 2-byte hex codec |
+ +---------+-----------+-----------+-----------------------------+
+ |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
+ +---------+-----------+-----------+-----------------------------+
+
+- Some operating systems now support the concept of a default Unicode
+ encoding for file system operations. Notably, Windows supports 'mbcs'
+ as the default. The Macintosh will also adopt this concept in the medium
+ term, although the default encoding for that platform will be other than
+ 'mbcs'.
+
+ On operating system that support non-ASCII filenames, it is common for
+ functions that return filenames (such as os.listdir()) to return Python
+ string objects pre-encoded using the default file system encoding for
+ the platform. As this encoding is likely to be different from Python's
+ default encoding, converting this name to a Unicode object before passing
+ it back to the Operating System would result in a Unicode error, as Python
+ would attempt to use its default encoding (generally ASCII) rather than
+ the default encoding for the file system.
+
+ In general, this change simply removes surprises when working with
+ Unicode and the file system, making these operations work as you expect,
+ increasing the transparency of Unicode objects in this context.
+ See [????] for more details, including examples.
+
+- Float (and complex) literals in source code were evaluated to full
+ precision only when running from a .py file; the same code loaded from a
+ .pyc (or .pyo) file could suffer numeric differences starting at about the
+ 12th significant decimal digit. For example, on a machine with IEEE-754
+ floating arithmetic,
+
+ x = 9007199254740992.0
+ print long(x)
+
+ printed 9007199254740992 if run directly from .py, but 9007199254740000
+ if from a compiled (.pyc or .pyo) file. This was due to marshal using
+ str(float) instead of repr(float) when building code objects. marshal
+ now uses repr(float) instead, which should reproduce floats to full
+ machine precision (assuming the platform C float<->string I/O conversion
+ functions are of good quality).
+
+ This may cause floating-point results to change in some cases, and
+ usually for the better, but may also cause numerically unstable
+ algorithms to break.
+
+- The implementation of dicts suffers fewer collisions, which has speed
+ benefits. However, the order in which dict entries appear in dict.keys(),
+ dict.values() and dict.items() may differ from previous releases for a
+ given dict. Nothing is defined about this order, so no program should
+ rely on it. Nevertheless, it's easy to write test cases that rely on the
+ order by accident, typically because of printing the str() or repr() of a
+ dict to an "expected results" file. See Lib/test/test_support.py's new
+ sortdict(dict) function for a simple way to display a dict in sorted
+ order.
+
+- Many other small changes to dicts were made, resulting in faster
+ operation along the most common code paths.
+
+- Dictionary objects now support the "in" operator: "x in dict" means
+ the same as dict.has_key(x).
+
+- The update() method of dictionaries now accepts generic mapping
+ objects. Specifically the argument object must support the .keys()
+ and __getitem__() methods. This allows you to say, for example,
+ {}.update(UserDict())
+
+- Iterators were added; this is a generalized way of providing values
+ to a for loop. See PEP 234. There's a new built-in function iter()
+ to return an iterator. There's a new protocol to get the next value
+ from an iterator using the next() method (in Python) or the
+ tp_iternext slot (in C). There's a new protocol to get iterators
+ using the __iter__() method (in Python) or the tp_iter slot (in C).
+ Iterating (i.e. a for loop) over a dictionary generates its keys.
+ Iterating over a file generates its lines.
+
+- The following functions were generalized to work nicely with iterator
+ arguments::
+
+ map(), filter(), reduce(), zip()
+ list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
+ max(), min()
+ join() method of strings
+ extend() method of lists
+ 'x in y' and 'x not in y' (PySequence_Contains() in C API)
+ operator.countOf() (PySequence_Count() in C API)
+ right-hand side of assignment statements with multiple targets, such as ::
+ x, y, z = some_iterable_object_returning_exactly_3_values
+
+- Accessing module attributes is significantly faster (for example,
+ random.random or os.path or yourPythonModule.yourAttribute).
+
+- Comparing dictionary objects via == and != is faster, and now works even
+ if the keys and values don't support comparisons other than ==.
+
+- Comparing dictionaries in ways other than == and != is slower: there were
+ insecurities in the dict comparison implementation that could cause Python
+ to crash if the element comparison routines for the dict keys and/or
+ values mutated the dicts. Making the code bulletproof slowed it down.
+
+- Collisions in dicts are resolved via a new approach, which can help
+ dramatically in bad cases. For example, looking up every key in a dict
+ d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
+ faster now. Thanks to Christian Tismer for pointing out the cause and
+ the nature of an effective cure (last December! better late than never).
+
+- repr() is much faster for large containers (dict, list, tuple).
+
+
+Library
+-------
+
+- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
+ were added to the string module. These a locale-independent
+ constants, unlike letters, lowercase, and uppercase. These are now
+ use in appropriate locations in the standard library.
+
+- The flags used in dlopen calls can now be configured using
+ sys.setdlopenflags and queried using sys.getdlopenflags.
+
+- Fredrik Lundh's xmlrpclib is now a standard library module. This
+ provides full client-side XML-RPC support. In addition,
+ Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
+ one asyncore-based). Thanks to Eric Raymond for the documentation.
+
+- The xrange() object is simplified: it no longer supports slicing,
+ repetition, comparisons, efficient 'in' checking, the tolist()
+ method, or the start, stop and step attributes. See PEP 260.
+
+- A new function fnmatch.filter to filter lists of file names was added.
+
+- calendar.py uses month and day names based on the current locale.
+
+- strop is now *really* obsolete (this was announced before with 1.6),
+ and issues DeprecationWarning when used (except for the four items
+ that are still imported into string.py).
+
+- Cookie.py now sorts key+value pairs by key in output strings.
+
+- pprint.isrecursive(object) didn't correctly identify recursive objects.
+ Now it does.
+
+- pprint functions now much faster for large containers (tuple, list, dict).
+
+- New 'q' and 'Q' format codes in the struct module, corresponding to C
+ types "long long" and "unsigned long long" (on Windows, __int64). In
+ native mode, these can be used only when the platform C compiler supports
+ these types (when HAVE_LONG_LONG is #define'd by the Python config
+ process), and then they inherit the sizes and alignments of the C types.
+ In standard mode, 'q' and 'Q' are supported on all platforms, and are
+ 8-byte integral types.
+
+- The site module installs a new built-in function 'help' that invokes
+ pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
+ it displays a message reminding the user to use 'help()' or
+ 'help(object)'.
+
+Tests
+-----
+
+- New test_mutants.py runs dict comparisons where the key and value
+ comparison operators mutate the dicts randomly during comparison. This
+ rapidly causes Python to crash under earlier releases (not for the faint
+ of heart: it can also cause Win9x to freeze or reboot!).
+
+- New test_pprint.py verifies that pprint.isrecursive() and
+ pprint.isreadable() return sensible results. Also verifies that simple
+ cases produce correct output.
+
+C API
+-----
+
+- Removed the unused last_is_sticky argument from the internal
+ _PyTuple_Resize(). If this affects you, you were cheating.
+
What's New in Python 2.1 (final)?
=================================
Modified: python/trunk/Misc/NEWS
==============================================================================
--- python/trunk/Misc/NEWS (original)
+++ python/trunk/Misc/NEWS Mon Mar 20 07:30:41 2006
@@ -1001,5293 +1001,6 @@
- Fixed a display glitch in Pynche, which could cause the right arrow to
wiggle over by a pixel.
-What's New in Python 2.4 final?
-===============================
-
-*Release date: 30-NOV-2004*
-
-Core and builtins
------------------
-
-- Bug 875692: Improve signal handling, especially when using threads, by
- forcing an early re-execution of PyEval_EvalFrame() "periodic" code when
- things_to_do is not cleared by Py_MakePendingCalls().
-
-
-What's New in Python 2.4 (release candidate 1)
-==============================================
-
-*Release date: 18-NOV-2004*
-
-Core and builtins
------------------
-
-- Bug 1061968: Fixes in 2.4a3 to address thread bug 1010677 reintroduced
- the years-old thread shutdown race bug 225673. Numeric history lesson
- aside, all bugs in all three reports are fixed now.
-
-
-Library
--------
-
-- Bug 1052242: If exceptions are raised by an atexit handler function an
- attempt is made to execute the remaining handlers. The last exception
- raised is re-raised.
-
-- ``doctest``'s new support for adding ``pdb.set_trace()`` calls to
- doctests was broken in a dramatic but shallow way. Fixed.
-
-- Bug 1065388: ``calendar``'s ``day_name``, ``day_abbr``, ``month_name``,
- and ``month_abbr`` attributes emulate sequences of locale-correct
- spellings of month and day names. Because the locale can change at
- any time, the correct spelling is recomputed whenever one of these is
- indexed. In the worst case, the index may be a slice object, so these
- recomputed every day or month name each time they were indexed. This is
- much slower than necessary in the usual case, when the index is just an
- integer. In that case, only the single spelling needed is recomputed
- now; and, when the index is a slice object, only the spellings needed
- by the slice are recomputed now.
-
-- Patch 1061679: Added ``__all__`` to pickletools.py.
-
-Build
------
-
-- Bug 1034277 / Patch 1035255: Remove compilation of core against CoreServices
- and CoreFoundation on OS X. Involved removing PyMac_GetAppletScriptFile()
- which has no known users. Thanks Bob Ippolito.
-
-C API
------
-
-- The PyRange_New() function is deprecated.
-
-
-What's New in Python 2.4 beta 2?
-================================
-
-*Release date: 03-NOV-2004*
-
-License
--------
-
-The Python Software Foundation changed the license under which Python
-is released, to remove Python version numbers. There were no other
-changes to the license. So, for example, wherever the license for
-Python 2.3 said "Python 2.3", the new license says "Python". The
-intent is to make it possible to refer to the PSF license in a more
-durable way. For example, some people say they're confused by that
-the Open Source Initiative's entry for the Python Software Foundation
-License::
-
- http://www.opensource.org/licenses/PythonSoftFoundation.php
-
-says "Python 2.1.1" all over it, wondering whether it applies only
-to Python 2.1.1.
-
-The official name of the new license is the Python Software Foundation
-License Version 2.
-
-Core and builtins
------------------
-
-- Bug #1055820 Cyclic garbage collection was not protecting against that
- calling a live weakref to a piece of cyclic trash could resurrect an
- insane mutation of the trash if any Python code ran during gc (via
- running a dead object's __del__ method, running another callback on a
- weakref to a dead object, or via any Python code run in any other thread
- that managed to obtain the GIL while a __del__ or callback was running
- in the thread doing gc). The most likely symptom was "impossible"
- ``AttributeError`` exceptions, appearing seemingly at random, on weakly
- referenced objects. The cure was to clear all weakrefs to unreachable
- objects before allowing any callbacks to run.
-
-- Bug #1054139 _PyString_Resize() now invalidates its cached hash value.
-
-Extension Modules
------------------
-
-- Bug #1048870: the compiler now generates distinct code objects for
- functions with identical bodies. This was producing confusing
- traceback messages which pointed to the function where the code
- object was first defined rather than the function being executed.
-
-Library
--------
-
-- Patch #1056967 changes the semantics of Template.safe_substitute() so that
- no ValueError is raised on an 'invalid' match group. Now the delimiter is
- returned.
-
-- Bug #1052503 pdb.runcall() was not passing along keyword arguments.
-
-- Bug #902037: XML.sax.saxutils.prepare_input_source() now combines relative
- paths with a base path before checking os.path.isfile().
-
-- The whichdb module can now be run from the command line.
-
-- Bug #1045381: time.strptime() can now infer the date using %U or %W (week of
- the year) when the day of the week and year are also specified.
-
-- Bug #1048816: fix bug in Ctrl-K at start of line in curses.textpad.Textbox
-
-- Bug #1017553: fix bug in tarfile.filemode()
-
-- Patch #737473: fix bug that old source code is shown in tracebacks even if
- the source code is updated and reloaded.
-
-Build
------
-
-- Patch #1044395: --enable-shared is allowed in FreeBSD also.
-
-What's New in Python 2.4 beta 1?
-================================
-
-*Release date: 15-OCT-2004*
-
-Core and builtins
------------------
-
-- Patch #975056: Restartable signals were not correctly disabled on
- BSD systems. Consistently use PyOS_setsig() instead of signal().
-
-- The internal portable implementation of thread-local storage (TLS), used
- by the ``PyGILState_Ensure()``/``PyGILState_Release()`` API, was not
- thread-correct. This could lead to a variety of problems, up to and
- including segfaults. See bug 1041645 for an example.
-
-- Added a command line option, -m module, which searches sys.path for the
- module and then runs it. (Contributed by Nick Coghlan.)
-
-- The bytecode optimizer now folds tuples of constants into a single
- constant.
-
-- SF bug #513866: Float/long comparison anomaly. Prior to 2.4b1, when
- an integer was compared to a float, the integer was coerced to a float.
- That could yield spurious overflow errors (if the integer was very
- large), and to anomalies such as
- ``long(1e200)+1 == 1e200 == long(1e200)-1``. Coercion to float is no
- longer performed, and cases like ``long(1e200)-1 < 1e200``,
- ``long(1e200)+1 > 1e200`` and ``(1 << 20000) > 1e200`` are computed
- correctly now.
-
-Extension modules
------------------
-
-- ``collections.deque`` objects didn't play quite right with garbage
- collection, which could lead to a segfault in a release build, or
- an assert failure in a debug build. Also, added overflow checks,
- better detection of mutation during iteration, and shielded deque
- comparisons from unusual subclass overrides of the __iter__() method.
-
-Library
--------
-
-- Patch 1046644: distutils build_ext grew two new options - --swig for
- specifying the swig executable to use, and --swig-opts to specify
- options to pass to swig. --swig-opts="-c++" is the new way to spell
- --swig-cpp.
-
-- Patch 983206: distutils now obeys environment variable LDSHARED, if
- it is set.
-
-- Added Peter Astrand's subprocess.py module. See PEP 324 for details.
-
-- time.strptime() now properly escapes timezones and all other locale-specific
- strings for regex-specific symbols. Was breaking under Japanese Windows when
- the timezone was specified as "Tokyo (standard time)".
- Closes bug #1039270.
-
-- Updates for the email package:
-
- + email.Utils.formatdate() grew a 'usegmt' argument for HTTP support.
- + All deprecated APIs that in email 2.x issued warnings have been removed:
- _encoder argument to the MIMEText constructor, Message.add_payload(),
- Utils.dump_address_pair(), Utils.decode(), Utils.encode()
- + New deprecations: Generator.__call__(), Message.get_type(),
- Message.get_main_type(), Message.get_subtype(), the 'strict' argument to
- the Parser constructor. These will be removed in email 3.1.
- + Support for Python earlier than 2.3 has been removed (see PEP 291).
- + All defect classes have been renamed to end in 'Defect'.
- + Some FeedParser fixes; also a MultipartInvariantViolationDefect will be
- added to messages that claim to be multipart but really aren't.
- + Updates to documentation.
-
-- re's findall() and finditer() functions now take an optional flags argument
- just like the compile(), search(), and match() functions. Also, documented
- the previously existing start and stop parameters for the findall() and
- finditer() methods of regular expression objects.
-
-- rfc822 Messages now support iterating over the headers.
-
-- The (undocumented) tarfile.Tarfile.membernames has been removed;
- applications should use the getmember function.
-
-- httplib now offers symbolic constants for the HTTP status codes.
-
-- SF bug #1028306: Trying to compare a ``datetime.date`` to a
- ``datetime.datetime`` mistakenly compared only the year, month and day.
- Now it acts like a mixed-type comparison: ``False`` for ``==``,
- ``True`` for ``!=``, and raises ``TypeError`` for other comparison
- operators. Because datetime is a subclass of date, comparing only the
- base class (date) members can still be done, if that's desired, by
- forcing using of the approprate date method; e.g.,
- ``a_date.__eq__(a_datetime)`` is true if and only if the year, month
- and day members of ``a_date`` and ``a_datetime`` are equal.
-
-- bdist_rpm now supports command line options --force-arch,
- {pre,post}-install, {pre,post}-uninstall, and
- {prep,build,install,clean,verify}-script.
-
-- SF patch #998993: The UTF-8 and the UTF-16 stateful decoders now support
- decoding incomplete input (when the input stream is temporarily exhausted).
- ``codecs.StreamReader`` now implements buffering, which enables proper
- readline support for the UTF-16 decoders. ``codecs.StreamReader.read()``
- has a new argument ``chars`` which specifies the number of characters to
- return. ``codecs.StreamReader.readline()`` and
- ``codecs.StreamReader.readlines()`` have a new argument ``keepends``.
- Trailing "\n"s will be stripped from the lines if ``keepends`` is false.
-
-- The documentation for doctest is greatly expanded, and now covers all
- the new public features (of which there are many).
-
-- ``doctest.master`` was put back in, and ``doctest.testmod()`` once again
- updates it. This isn't good, because every ``testmod()`` call
- contributes to bloating the "hidden" state of ``doctest.master``, but
- some old code apparently relies on it. For now, all we can do is
- encourage people to stitch doctests together via doctest's unittest
- integration features instead.
-
-- httplib now handles ipv6 address/port pairs.
-
-- SF bug #1017864: ConfigParser now correctly handles default keys,
- processing them with ``ConfigParser.optionxform`` when supplied,
- consistent with the handling of config file entries and runtime-set
- options.
-
-- SF bug #997050: Document, test, & check for non-string values in
- ConfigParser. Moved the new string-only restriction added in
- rev. 1.65 to the SafeConfigParser class, leaving existing
- ConfigParser & RawConfigParser behavior alone, and documented the
- conditions under which non-string values work.
-
-Build
------
-
-- Building on darwin now includes /opt/local/include and /opt/local/lib for
- building extension modules. This is so as to include software installed as
- a DarwinPorts port <http://darwinports.opendarwin.org/>
-
-- pyport.h now defines a Py_IS_NAN macro. It works as-is when the
- platform C computes true for ``x != x`` if and only if X is a NaN.
- Other platforms can override the default definition with a platform-
- specific spelling in that platform's pyconfig.h. You can also override
- pyport.h's default Py_IS_INFINITY definition now.
-
-C API
------
-
-- SF patch 1044089: New function ``PyEval_ThreadsInitialized()`` returns
- non-zero if PyEval_InitThreads() has been called.
-
-- The undocumented and unused extern int ``_PyThread_Started`` was removed.
-
-- The C API calls ``PyInterpreterState_New()`` and ``PyThreadState_New()``
- are two of the very few advertised as being safe to call without holding
- the GIL. However, this wasn't true in a debug build, as bug 1041645
- demonstrated. In a debug build, Python redirects the ``PyMem`` family
- of calls to Python's small-object allocator, to get the benefit of
- its extra debugging capabilities. But Python's small-object allocator
- isn't threadsafe, relying on the GIL to avoid the expense of doing its
- own locking. ``PyInterpreterState_New()`` and ``PyThreadState_New()``
- call the platform ``malloc()`` directly now, regardless of build type.
-
-- PyLong_AsUnsignedLong[Mask] now support int objects as well.
-
-- SF patch #998993: ``PyUnicode_DecodeUTF8Stateful`` and
- ``PyUnicode_DecodeUTF16Stateful`` have been added, which implement stateful
- decoding.
-
-Tests
------
-
-- test__locale ported to unittest
-
-Mac
----
-
-- ``plistlib`` now supports non-dict root objects. There is also a new
- interface for reading and writing plist files: ``readPlist(pathOrFile)``
- and ``writePlist(rootObject, pathOrFile)``
-
-Tools/Demos
------------
-
-- The text file comparison scripts ``ndiff.py`` and ``diff.py`` now
- read the input files in universal-newline mode. This spares them
- from consuming a great deal of time to deduce the useless result that,
- e.g., a file with Windows line ends and a file with Linux line ends
- have no lines in common.
-
-
-What's New in Python 2.4 alpha 3?
-=================================
-
-*Release date: 02-SEP-2004*
-
-Core and builtins
------------------
-
-- SF patch #1007189: ``from ... import ...`` statements now allow the name
- list to be surrounded by parentheses.
-
-- Some speedups for long arithmetic, thanks to Trevor Perrin. Gradeschool
- multiplication was sped a little by optimizing the C code. Gradeschool
- squaring was sped by about a factor of 2, by exploiting that about half
- the digit products are duplicates in a square. Because exponentiation
- uses squaring often, this also speeds long power. For example, the time
- to compute 17**1000000 dropped from about 14 seconds to 9 on my box due
- to this much. The cutoff for Karatsuba multiplication was raised,
- since gradeschool multiplication got quicker, and the cutoff was
- aggressively small regardless. The exponentiation algorithm was switched
- from right-to-left to left-to-right, which is more efficient for small
- bases. In addition, if the exponent is large, the algorithm now does
- 5 bits (instead of 1 bit) at a time. That cut the time to compute
- 17**1000000 on my box in half again, down to about 4.5 seconds.
-
-- OverflowWarning is no longer generated. PEP 237 scheduled this to
- occur in Python 2.3, but since OverflowWarning was disabled by default,
- nobody realized it was still being generated. On the chance that user
- code is still using them, the Python builtin OverflowWarning, and
- corresponding C API PyExc_OverflowWarning, will exist until Python 2.5.
-
-- Py_InitializeEx has been added.
-
-- Fix the order of application of decorators. The proper order is bottom-up;
- the first decorator listed is the last one called.
-
-- SF patch #1005778. Fix a seg fault if the list size changed while
- calling list.index(). This could happen if a rich comparison function
- modified the list.
-
-- The ``func_name`` (a.k.a. ``__name__``) attribute of user-defined
- functions is now writable.
-
-- code_new (a.k.a new.code()) now checks its arguments sufficiently
- carefully that passing them on to PyCode_New() won't trigger calls
- to Py_FatalError() or PyErr_BadInternalCall(). It is still the case
- that the returned code object might be entirely insane.
-
-- Subclasses of string can no longer be interned. The semantics of
- interning were not clear here -- a subclass could be mutable, for
- example -- and had bugs. Explicitly interning a subclass of string
- via intern() will raise a TypeError. Internal operations that attempt
- to intern a string subclass will have no effect.
-
-- Bug 1003935: xrange() could report bogus OverflowErrors. Documented
- what xrange() intends, and repaired tests accordingly.
-
-Extension modules
------------------
-
-- difflib now supports HTML side-by-side diff.
-
-- os.urandom has been added for systems that support sources of random
- data.
-
-- Patch 1012740: truncate() on a writeable cStringIO now resets the
- position to the end of the stream. This is consistent with the original
- StringIO module and avoids inadvertently resurrecting data that was
- supposed to have been truncated away.
-
-- Added socket.socketpair().
-
-- Added CurrentByteIndex, CurrentColumnNumber, CurrentLineNumber
- members to xml.parsers.expat.XMLParser object.
-
-- The mpz, rotor, and xreadlines modules, all deprecated in earlier
- versions of Python, have now been removed.
-
-Library
--------
-
-- Patch #934356: if a module defines __all__, believe that rather than using
- heuristics for filtering out imported names.
-
-- Patch #941486: added os.path.lexists(), which returns True for broken
- symlinks, unlike os.path.exists().
-
-- the random module now uses os.urandom() for seeding if it is available.
- Added a new generator based on os.urandom().
-
-- difflib and diff.py can now generate HTML.
-
-- bdist_rpm now includes version and release in the BuildRoot, and
- replaces - by ``_`` in version and release.
-
-- distutils build/build_scripts now has an -e option to specify the
- path to the Python interpreter for installed scripts.
-
-- PEP 292 classes Template and SafeTemplate are added to the string module.
-
-- tarfile now generates GNU tar files by default.
-
-- HTTPResponse has now a getheaders method.
-
-- Patch #1006219: let inspect.getsource handle '@' decorators. Thanks Simon
- Percivall.
-
-- logging.handlers.SMTPHandler.date_time has been removed;
- the class now uses email.Utils.formatdate to generate the time stamp.
-
-- A new function tkFont.nametofont was added to return an existing
- font. The Font class constructor now has an additional exists argument
- which, if True, requests to return/configure an existing font, rather
- than creating a new one.
-
-- Updated the decimal package's min() and max() methods to match the
- latest revision of the General Decimal Arithmetic Specification.
- Quiet NaNs are ignored and equal values are sorted based on sign
- and exponent.
-
-- The decimal package's Context.copy() method now returns deep copies.
-
-- Deprecated sys.exitfunc in favor of the atexit module. The sys.exitfunc
- attribute will be kept around for backwards compatibility and atexit
- will just become the one preferred way to do it.
-
-- patch #675551: Add get_history_item and replace_history_item functions
- to the readline module.
-
-- bug #989672: pdb.doc and the help messages for the help_d and help_u methods
- of the pdb.Pdb class gives have been corrected. d(own) goes to a newer
- frame, u(p) to an older frame, not the other way around.
-
-- bug #990669: os.path.realpath() will resolve symlinks before normalizing the
- path, as normalizing the path may alter the meaning of the path if it
- contains symlinks.
-
-- bug #851123: shutil.copyfile will raise an exception when trying to copy a
- file onto a link to itself. Thanks Gregory Ball.
-
-- bug #570300: Fix inspect to resolve file locations using os.path.realpath()
- so as to properly list all functions in a module when the module itself is
- reached through a symlink. Thanks Johannes Gijsbers.
-
-- doctest refactoring continued. See the docs for details. As part of
- this effort, some old and little- (never?) used features are now
- deprecated: the Tester class, the module is_private() function, and the
- isprivate argument to testmod(). The Tester class supplied a feeble
- "by hand" way to combine multiple doctests, if you knew exactly what
- you were doing. The newer doctest features for unittest integration
- already did a better job of that, are stronger now than ever, and the
- new DocTestRunner class is a saner foundation if you want to do it by
- hand. The "private name" filtering gimmick was a mistake from the
- start, and testmod() changed long ago to ignore it by default. If
- you want to filter out tests, the new DocTestFinder class can be used
- to return a list of all doctests, and you can filter that list by
- any computable criteria before passing it to a DocTestRunner instance.
-
-- Bug #891637, patch #1005466: fix inspect.getargs() crash on def foo((bar)).
-
-Tools/Demos
------------
-
-- IDLE's shortcut keys for windows are now case insensitive so that
- Control-V works the same as Control-v.
-
-- pygettext.py: Generate POT-Creation-Date header in ISO format.
-
-Build
------
-
-- Backward incompatibility: longintrepr.h now triggers a compile-time
- error if SHIFT (the number of bits in a Python long "digit") isn't
- divisible by 5. This new requirement allows simple code for the new
- 5-bits-at-a-time long_pow() implementation. If necessary, the
- restriction could be removed (by complicating long_pow(), or by
- falling back to the 1-bit-at-a-time algorithm), but there are no
- plans to do so.
-
-- bug #991962: When building with --disable-toolbox-glue on Darwin no
- attempt to build Mac-specific modules occurs.
-
-- The --with-tsc flag to configure to enable VM profiling with the
- processor's timestamp counter now works on PPC platforms.
-
-- patch #1006629: Define _XOPEN_SOURCE to 500 on Solaris 8/9 to match
- GCC's definition and avoid redefinition warnings.
-
-- Detect pthreads support (provided by gnu pth pthread emulation) on
- GNU/k*BSD systems.
-
-- bug #1005737, #1007249: Fixed several build problems and warnings
- found on old/legacy C compilers of HP-UX, IRIX and Tru64.
-
-C API
------
-
-..
-
-Documentation
--------------
-
-- patch #1005936, bug #1009373: fix index entries which contain
- an underscore when viewed with Acrobat.
-
-- bug #990669: os.path.normpath may alter the meaning of a path if
- it contains symbolic links. This has been documented in a comment
- since 1992, but is now in the library reference as well.
-
-New platforms
--------------
-
-- FreeBSD 6 is now supported.
-
-Tests
------
-
-..
-
-Windows
--------
-
-- Boosted the stack reservation for python.exe and pythonw.exe from
- the default 1MB to 2MB. Stack frames under VC 7.1 for 2.4 are enough
- bigger than under VC 6.0 for 2.3.4 that deeply recursive progams
- within the default sys.getrecursionlimit() default value of 1000 were
- able to suffer undetected C stack overflows. The standard test program
- test_compiler was one such program. If a Python process on Windows
- "just vanishes" without a trace, and without an error message of any
- kind, but with an exit code of 128, undetected stack overflow may be
- the problem.
-
-Mac
----
-
-..
-
-
-What's New in Python 2.4 alpha 2?
-=================================
-
-*Release date: 05-AUG-2004*
-
-Core and builtins
------------------
-
-- Patch #980695: Implements efficient string concatenation for statements
- of the form s=s+t and s+=t. This will vary across implementations.
- Accordingly, the str.join() method is strongly preferred for performance
- sensitive code.
-
-- PEP-0318, Function Decorators have been added to the language. These are
- implemented using the Java-style @decorator syntax, like so::
-
- @staticmethod
- def foo(bar):
-
- (The PEP needs to be updated to reflect the current state)
-
-- When importing a module M raises an exception, Python no longer leaves M
- in sys.modules. Before 2.4a2 it did, and a subsequent import of M would
- succeed, picking up a module object from sys.modules reflecting as much
- of the initialization of M as completed before the exception was raised.
- Subsequent imports got no indication that M was in a partially-
- initialized state, and the importers could get into arbitrarily bad
- trouble as a result (the M they got was in an unintended state,
- arbitrarily far removed from M's author's intent). Now subsequent
- imports of M will continue raising exceptions (but if, for example, the
- source code for M is edited between import attempts, then perhaps later
- attempts will succeed, or raise a different exception).
-
- This can break existing code, but in such cases the code was probably
- working before by accident. In the Python source, the only case of
- breakage discovered was in a test accidentally relying on a damaged
- module remaining in sys.modules. Cases are also known where tests
- deliberately provoking import errors remove damaged modules from
- sys.modules themselves, and such tests will break now if they do an
- unconditional del sys.modules[M].
-
-- u'%s' % obj will now try obj.__unicode__() first and fallback to
- obj.__str__() if no __unicode__ method can be found.
-
-- Patch #550732: Add PyArg_VaParseTupleAndKeywords(). Analogous to
- PyArg_VaParse(). Both are now documented. Thanks Greg Chapman.
-
-- Allow string and unicode return types from .encode()/.decode()
- methods on string and unicode objects. Added unicode.decode()
- which was missing for no apparent reason.
-
-- An attempt to fix the mess that is Python's behaviour with
- signal handlers and threads, complicated by readline's behaviour.
- It's quite possible that there are still bugs here.
-
-- Added C macros Py_CLEAR and Py_VISIT to ease the implementation of
- types that support garbage collection.
-
-- Compiler now treats None as a constant.
-
-- The type of values returned by __int__, __float__, __long__,
- __oct__, and __hex__ are now checked. Returning an invalid type
- will cause a TypeError to be raised. This matches the behavior of
- Jython.
-
-- Implemented bind_textdomain_codeset() in locale module.
-
-- Added a workaround for proper string operations in BSDs. str.split
- and str.is* methods can now work correctly with UTF-8 locales.
-
-- Bug #989185: unicode.iswide() and unicode.width() is dropped and
- the East Asian Width support is moved to unicodedata extension
- module.
-
-- Patch #941229: The source code encoding in interactive mode
- now refers sys.stdin.encoding not just ISO-8859-1 anymore. This
- allows for non-latin-1 users to write unicode strings directly.
-
-Extension modules
------------------
-
-- cpickle now supports the same keyword arguments as pickle.
-
-Library
--------
-
-- Added new codecs and aliases for ISO_8859-11, ISO_8859-16 and
- TIS-620
-
-- Thanks to Edward Loper, doctest has been massively refactored, and
- many new features were added. Full docs will appear later. For now
- the doctest module comments and new test cases give good coverage.
- The refactoring provides many hook points for customizing behavior
- (such as how to report errors, and how to compare expected to actual
- output). New features include a <BLANKLINE> marker for expected
- output containing blank lines, options to produce unified or context
- diffs when actual output doesn't match expectations, an option to
- normalize whitespace before comparing, and an option to use an
- ellipsis to signify "don't care" regions of output.
-
-- Tkinter now supports the wish -sync and -use options.
-
-- The following methods in time support passing of None: ctime(), gmtime(),
- and localtime(). If None is provided, the current time is used (the
- same as when the argument is omitted).
- [SF bug 658254, patch 663482]
-
-- nntplib does now allow to ignore a .netrc file.
-
-- urllib2 now recognizes Basic authentication even if other authentication
- schemes are offered.
-
-- Bug #1001053. wave.open() now accepts unicode filenames.
-
-- gzip.GzipFile has a new fileno() method, to retrieve the handle of the
- underlying file object (provided it has a fileno() method). This is
- needed if you want to use os.fsync() on a GzipFile.
-
-- imaplib has two new methods: deleteacl and myrights.
-
-- nntplib has two new methods: description and descriptions. They
- use a more RFC-compliant way of getting a newsgroup description.
-
-- Bug #993394. Fix a possible red herring of KeyError in 'threading' being
- raised during interpreter shutdown from a registered function with atexit
- when dummy_threading is being used.
-
-- Bug #857297/Patch #916874. Fix an error when extracting a hard link
- from a tarfile.
-
-- Patch #846659. Fix an error in tarfile.py when using
- GNU longname/longlink creation.
-
-- The obsolete FCNTL.py has been deleted. The builtin fcntl module
- has been available (on platforms that support fcntl) since Python
- 1.5a3, and all FCNTL.py did is export fcntl's names, after generating
- a deprecation warning telling you to use fcntl directly.
-
-- Several new unicode codecs are added: big5hkscs, euc_jis_2004,
- iso2022_jp_2004, shift_jis_2004.
-
-- Bug #788520. Queue.{get, get_nowait, put, put_nowait} have new
- implementations, exploiting Conditions (which didn't exist at the time
- Queue was introduced). A minor semantic change is that the Full and
- Empty exceptions raised by non-blocking calls now occur only if the
- queue truly was full or empty at the instant the queue was checked (of
- course the Queue may no longer be full or empty by the time a calling
- thread sees those exceptions, though). Before, the exceptions could
- also be raised if it was "merely inconvenient" for the implementation
- to determine the true state of the Queue (because the Queue was locked
- by some other method in progress).
-
-- Bugs #979794 and #980117: difflib.get_grouped_opcodes() now handles the
- case of comparing two empty lists. This affected both context_diff() and
- unified_diff(),
-
-- Bug #980938: smtplib now prints debug output to sys.stderr.
-
-- Bug #930024: posixpath.realpath() now handles infinite loops in symlinks by
- returning the last point in the path that was not part of any loop. Thanks
- AM Kuchling.
-
-- Bug #980327: ntpath not handles compressing erroneous slashes between the
- drive letter and the rest of the path. Also clearly handles UNC addresses now
- as well. Thanks Paul Moore.
-
-- bug #679953: zipfile.py should now work for files over 2 GB. The packed data
- for file sizes (compressed and uncompressed) was being stored as signed
- instead of unsigned.
-
-- decimal.py now only uses signals in the IBM spec. The other conditions are
- no longer part of the public API.
-
-- codecs module now has two new generic APIs: encode() and decode()
- which don't restrict the return types (unlike the unicode and
- string methods of the same name).
-
-- Non-blocking SSL sockets work again; they were broken in Python 2.3.
- SF patch 945642.
-
-- doctest unittest integration improvements:
-
- o Improved the unitest test output for doctest-based unit tests
-
- o Can now pass setUp and tearDown functions when creating
- DocTestSuites.
-
-- The threading module has a new class, local, for creating objects
- that provide thread-local data.
-
-- Bug #990307: when keep_empty_values is True, cgi.parse_qsl()
- no longer returns spurious empty fields.
-
-- Implemented bind_textdomain_codeset() in gettext module.
-
-- Introduced in gettext module the l*gettext() family of functions,
- which return translation strings encoded in the preferred encoding,
- as informed by locale module's getpreferredencoding().
-
-- optparse module (and tests) upgraded to Optik 1.5a1. Changes:
-
- - Add expansion of default values in help text: the string
- "%default" in an option's help string is expanded to str() of
- that option's default value, or "none" if no default value.
-
- - Bug #955889: option default values that happen to be strings are
- now processed in the same way as values from the command line; this
- allows generation of nicer help when using custom types. Can
- be disabled with parser.set_process_default_values(False).
-
- - Bug #960515: don't crash when generating help for callback
- options that specify 'type', but not 'dest' or 'metavar'.
-
- - Feature #815264: change the default help format for short options
- that take an argument from e.g. "-oARG" to "-o ARG"; add
- set_short_opt_delimiter() and set_long_opt_delimiter() methods to
- HelpFormatter to allow (slight) customization of the formatting.
-
- - Patch #736940: internationalize Optik: all built-in user-
- targeted literal strings are passed through gettext.gettext(). (If
- you want translations (.po files), they're not included with Python
- -- you'll find them in the Optik source distribution from
- http://optik.sourceforge.net/ .)
-
- - Bug #878453: respect $COLUMNS environment variable for
- wrapping help output.
-
- - Feature #988122: expand "%prog" in the 'description' passed
- to OptionParser, just like in the 'usage' and 'version' strings.
- (This is *not* done in the 'description' passed to OptionGroup.)
-
-C API
------
-
-- PyImport_ExecCodeModule() and PyImport_ExecCodeModuleEx(): if an
- error occurs while loading the module, these now delete the module's
- entry from sys.modules. All ways of loading modules eventually call
- one of these, so this is an error-case change in semantics for all
- ways of loading modules. In rare cases, a module loader may wish
- to keep a module object in sys.modules despite that the module's
- code cannot be executed. In such cases, the module loader must
- arrange to reinsert the name and module object in sys.modules.
- PyImport_ReloadModule() has been changed to reinsert the original
- module object into sys.modules if the module reload fails, so that
- its visible semantics have not changed.
-
-- A large pile of datetime field-extraction macros is now documented,
- thanks to Anthony Tuininga (patch #986010).
-
-Documentation
--------------
-
-- Improved the tutorial on creating types in C.
-
- - point out the importance of reassigning data members before
- assigning their values
-
- - correct my misconception about return values from visitprocs. Sigh.
-
- - mention the labor saving Py_VISIT and Py_CLEAR macros.
-
-- Major rewrite of the math module docs, to address common confusions.
-
-Tests
------
-
-- The test data files for the decimal test suite are now installed on
- platforms that use the Makefile.
-
-- SF patch 995225: The test file testtar.tar accidentally contained
- CVS keywords (like $Id$), which could cause spurious failures in
- test_tarfile.py depending on how the test file was checked out.
-
-
-What's New in Python 2.4 alpha 1?
-=================================
-
-*Release date: 08-JUL-2004*
-
-Core and builtins
------------------
-
-- weakref.ref is now the type object also known as
- weakref.ReferenceType; it can be subclassed like any other new-style
- class. There's less per-entry overhead in WeakValueDictionary
- objects now (one object instead of three).
-
-- Bug #951851: Python crashed when reading import table of certain
- Windows DLLs.
-
-- Bug #215126. The locals argument to eval(), execfile(), and exec now
- accept any mapping type.
-
-- marshal now shares interned strings. This change introduces
- a new .pyc magic.
-
-- Bug #966623. classes created with type() in an exec(, {}) don't
- have a __module__, but code in typeobject assumed it would always
- be there.
-
-- Python no longer relies on the LC_NUMERIC locale setting to be
- the "C" locale; as a result, it no longer tries to prevent changing
- the LC_NUMERIC category.
-
-- Bug #952807: Unpickling pickled instances of subclasses of
- datetime.date, datetime.datetime and datetime.time could yield insane
- objects. Thanks to Jiwon Seo for a fix.
-
-- Bug #845802: Python crashes when __init__.py is a directory.
-
-- Unicode objects received two new methods: iswide() and width().
- These query East Asian width information, as specified in Unicode
- TR11.
-
-- Improved the tuple hashing algorithm to give fewer collisions in
- common cases. Fixes bug #942952.
-
-- Implemented generator expressions (PEP 289). Coded by Jiwon Seo.
-
-- Enabled the profiling of C extension functions (and builtins) - check
- new documentation and modified profile and bdb modules for more details
-
-- Set file.name to the object passed to open (instead of a new string)
-
-- Moved tracebackobject into traceback.h and renamed to PyTracebackObject
-
-- Optimized the byte coding for multiple assignments like "a,b=b,a" and
- "a,b,c=1,2,3". Improves their speed by 25% to 30%.
-
-- Limit the nested depth of a tuple for the second argument to isinstance()
- and issubclass() to the recursion limit of the interpreter.
- Fixes bug #858016 .
-
-- Optimized dict iterators, creating separate types for each
- and having them reveal their length. Also optimized the
- methods: keys(), values(), and items().
-
-- Implemented a newcode opcode, LIST_APPEND, that simplifies
- the generated bytecode for list comprehensions and further
- improves their performance (about 35%).
-
-- Implemented rich comparisons for floats, which seems to make
- comparisons involving NaNs somewhat less surprising when the
- underlying C compiler actually implements C99 semantics.
-
-- Optimized list.extend() to save memory and no longer create
- intermediate sequences. Also, extend() now pre-allocates the
- needed memory whenever the length of the iterable is known in
- advance -- this halves the time to extend the list.
-
-- Optimized list resize operations to make fewer calls to the system
- realloc(). Significantly speeds up list appends, list pops,
- list comprehensions, and the list constructor (when the input iterable
- length is not known).
-
-- Changed the internal list over-allocation scheme. For larger lists,
- overallocation ranged between 3% and 25%. Now, it is a constant 12%.
- For smaller lists (n<8), overallocation was upto eight elements. Now,
- the overallocation is no more than three elements -- this improves space
- utilization for applications that have large numbers of small lists.
-
-- Most list bodies now get re-used rather than freed. Speeds up list
- instantiation and deletion by saving calls to malloc() and free().
-
-- The dict.update() method now accepts all the same argument forms
- as the dict() constructor. This now includes item lists and/or
- keyword arguments.
-
-- Support for arbitrary objects supporting the read-only buffer
- interface as the co_code field of code objects (something that was
- only possible to create from C code) has been removed.
-
-- Made omitted callback and None equivalent for weakref.ref() and
- weakref.proxy(); the None case wasn't handled correctly in all
- cases.
-
-- Fixed problem where PyWeakref_NewRef() and PyWeakref_NewProxy()
- assumed that initial existing entries in an object's weakref list
- would not be removed while allocating a new weakref object. Since
- GC could be invoked at that time, however, that assumption was
- invalid. In a truly obscure case of GC being triggered during
- creation for a new weakref object for an referent which already
- has a weakref without a callback which is only referenced from
- cyclic trash, a memory error can occur. This consistently created a
- segfault in a debug build, but provided less predictable behavior in
- a release build.
-
-- input() builtin function now respects compiler flags such as
- __future__ statements. SF patch 876178.
-
-- Removed PendingDeprecationWarning from apply(). apply() remains
- deprecated, but the nuisance warning will not be issued.
-
-- At Python shutdown time (Py_Finalize()), 2.3 called cyclic garbage
- collection twice, both before and after tearing down modules. The
- call after tearing down modules has been disabled, because too much
- of Python has been torn down then for __del__ methods and weakref
- callbacks to execute sanely. The most common symptom was a sequence
- of uninformative messages on stderr when Python shut down, produced
- by threads trying to raise exceptions, but unable to report the nature
- of their problems because too much of the sys module had already been
- destroyed.
-
-- Removed FutureWarnings related to hex/oct literals and conversions
- and left shifts. (Thanks to Kalle Svensson for SF patch 849227.)
- This addresses most of the remaining semantic changes promised by
- PEP 237, except for repr() of a long, which still shows the trailing
- 'L'. The PEP appears to promise warnings for operations that
- changed semantics compared to Python 2.3, but this is not
- implemented; we've suffered through enough warnings related to
- hex/oct literals and I think it's best to be silent now.
-
-- For str and unicode objects, the ljust(), center(), and rjust()
- methods now accept an optional argument specifying a fill
- character other than a space.
-
-- When method objects have an attribute that can be satisfied either
- by the function object or by the method object, the function
- object's attribute usually wins. Christian Tismer pointed out that
- that this is really a mistake, because this only happens for special
- methods (like __reduce__) where the method object's version is
- really more appropriate than the function's attribute. So from now
- on, all method attributes will have precedence over function
- attributes with the same name.
-
-- Critical bugfix, for SF bug 839548: if a weakref with a callback,
- its callback, and its weakly referenced object, all became part of
- cyclic garbage during a single run of garbage collection, the order
- in which they were torn down was unpredictable. It was possible for
- the callback to see partially-torn-down objects, leading to immediate
- segfaults, or, if the callback resurrected garbage objects, to
- resurrect insane objects that caused segfaults (or other surprises)
- later. In one sense this wasn't surprising, because Python's cyclic gc
- had no knowledge of Python's weakref objects. It does now. When
- weakrefs with callbacks become part of cyclic garbage now, those
- weakrefs are cleared first. The callbacks don't trigger then,
- preventing the problems. If you need callbacks to trigger, then just
- as when cyclic gc is not involved, you need to write your code so
- that weakref objects outlive the objects they weakly reference.
-
-- Critical bugfix, for SF bug 840829: if cyclic garbage collection
- happened to occur during a weakref callback for a new-style class
- instance, subtle memory corruption was the result (in a release build;
- in a debug build, a segfault occurred reliably very soon after).
- This has been repaired.
-
-- Compiler flags set in PYTHONSTARTUP are now active in __main__.
-
-- Added two builtin types, set() and frozenset().
-
-- Added a reversed() builtin function that returns a reverse iterator
- over a sequence.
-
-- Added a sorted() builtin function that returns a new sorted list
- from any iterable.
-
-- CObjects are now mutable (on the C level) through PyCObject_SetVoidPtr.
-
-- list.sort() now supports three keyword arguments: cmp, key, and reverse.
- The key argument can be a function of one argument that extracts a
- comparison key from the original record: mylist.sort(key=str.lower).
- The reverse argument is a boolean value and if True will change the
- sort order as if the comparison arguments were reversed. In addition,
- the documentation has been amended to provide a guarantee that all sorts
- starting with Py2.3 are guaranteed to be stable (the relative order of
- records with equal keys is unchanged).
-
-- Added test whether wchar_t is signed or not. A signed wchar_t is not
- usable as internal unicode type base for Py_UNICODE since the
- unicode implementation assumes an unsigned type.
-
-- Fixed a bug in the cache of length-one Unicode strings that could
- lead to a seg fault. The specific problem occurred when an earlier,
- non-fatal error left an uninitialized Unicode object in the
- freelist.
-
-- The % formatting operator now supports '%F' which is equivalent to
- '%f'. This has always been documented but never implemented.
-
-- complex(obj) could leak a little memory if obj wasn't a string or
- number.
-
-- zip() with no arguments now returns an empty list instead of raising
- a TypeError exception.
-
-- obj.__contains__() now returns True/False instead of 1/0. SF patch
- 820195.
-
-- Python no longer tries to be smart about recursive comparisons.
- When comparing containers with cyclic references to themselves it
- will now just hit the recursion limit. See SF patch 825639.
-
-- str and unicode builtin types now have an rsplit() method that is
- same as split() except that it scans the string from the end
- working towards the beginning. See SF feature request 801847.
-
-- Fixed a bug in object.__reduce_ex__ when using protocol 2. Failure
- to clear the error when attempts to get the __getstate__ attribute
- fail caused intermittent errors and odd behavior.
-
-- buffer objects based on other objects no longer cache a pointer to
- the data and the data length. Instead, the appropriate tp_as_buffer
- method is called as necessary.
-
-- fixed: if a file is opened with an explicit buffer size >= 1, repeated
- close() calls would attempt to free() the buffer already free()ed on
- the first call.
-
-
-Extension modules
------------------
-
-- Added socket.getservbyport(), and make the second argument in
- getservbyname() and getservbyport() optional.
-
-- time module code that deals with input POSIX timestamps will now raise
- ValueError if more than a second is lost in precision when the
- timestamp is cast to the platform C time_t type. There's no chance
- that the platform will do anything sensible with the result in such
- cases. This includes ctime(), localtime() and gmtime(). Assorted
- fromtimestamp() and utcfromtimestamp() methods in the datetime module
- were also protected. Closes bugs #919012 and 975996.
-
-- fcntl.ioctl now warns if the mutate flag is not specified.
-
-- nt now properly allows to refer to UNC roots, e.g. in nt.stat().
-
-- the weakref module now supports additional objects: array.array,
- sre.pattern_objects, file objects, and sockets.
-
-- operator.isMappingType() and operator.isSequenceType() now give
- fewer false positives.
-
-- socket.sslerror is now a subclass of socket.error . Also added
- socket.error to the socket module's C API.
-
-- Bug #920575: A problem where the _locale module segfaults on
- nl_langinfo(ERA) caused by GNU libc's illegal NULL return is fixed.
-
-- array objects now support the copy module. Also, their resizing
- scheme has been updated to match that used for list objects. This improves
- the performance (speed and memory usage) of append() operations.
- Also, array.array() and array.extend() now accept any iterable argument
- for repeated appends without needing to create another temporary array.
-
-- cStringIO.writelines() now accepts any iterable argument and writes
- the lines one at a time rather than joining them and writing once.
- Made a parallel change to StringIO.writelines(). Saves memory and
- makes suitable for use with generator expressions.
-
-- time.strftime() now checks that the values in its time tuple argument
- are within the proper boundaries to prevent possible crashes from the
- platform's C library implementation of strftime(). Can possibly
- break code that uses values outside the range that didn't cause
- problems previously (such as sitting day of year to 0). Fixes bug
- #897625.
-
-- The socket module now supports Bluetooth sockets, if the
- system has <bluetooth/bluetooth.h>
-
-- Added a collections module containing a new datatype, deque(),
- offering high-performance, thread-safe, memory friendly appends
- and pops on either side of the deque.
-
-- Several modules now take advantage of collections.deque() for
- improved performance: Queue, mutex, shlex, threading, and pydoc.
-
-- The operator module has two new functions, attrgetter() and
- itemgetter() which are useful for creating fast data extractor
- functions for map(), list.sort(), itertools.groupby(), and
- other functions that expect a function argument.
-
-- socket.SHUT_{RD,WR,RDWR} was added.
-
-- os.getsid was added.
-
-- The pwd module incorrectly advertised its struct type as
- struct_pwent; this has been renamed to struct_passwd. (The old name
- is still supported for backwards compatibility.)
-
-- The xml.parsers.expat module now provides Expat 1.95.7.
-
-- socket.IPPROTO_IPV6 was added.
-
-- readline.clear_history was added.
-
-- select.select() now accepts sequences for its first three arguments.
-
-- cStringIO now supports the f.closed attribute.
-
-- The signal module now exposes SIGRTMIN and SIGRTMAX (if available).
-
-- curses module now supports use_default_colors(). [patch #739124]
-
-- Bug #811028: ncurses.h breakage on FreeBSD/MacOS X
-
-- Bug #814613: INET_ADDRSTRLEN fix needed for all compilers on SGI
-
-- Implemented non-recursive SRE matching scheme (#757624).
-
-- Implemented (?(id/name)yes|no) support in SRE (#572936).
-
-- random.seed() with no arguments or None uses time.time() as a default
- seed. Modified to match Py2.2 behavior and use fractional seconds so
- that successive runs are more likely to produce different sequences.
-
-- random.Random has a new method, getrandbits(k), which returns an int
- with k random bits. This method is now an optional part of the API
- for user defined generators. Any generator that defines genrandbits()
- can now use randrange() for ranges with a length >= 2**53. Formerly,
- randrange would return only even numbers for ranges that large (see
- SF bug #812202). Generators that do not define genrandbits() now
- issue a warning when randrange() is called with a range that large.
-
-- itertools has a new function, groupby() for aggregating iterables
- into groups sharing the same key (as determined by a key function).
- It offers some of functionality of SQL's groupby keyword and of
- the Unix uniq filter.
-
-- itertools now has a new tee() function which produces two independent
- iterators from a single iterable.
-
-- itertools.izip() with no arguments now returns an empty iterator instead
- of raising a TypeError exception.
-
-- Fixed #853061: allow BZ2Compressor.compress() to receive an empty string
- as parameter.
-
-Library
--------
-
-- Added a new module: cProfile, a C profiler with the same interface as the
- profile module. cProfile avoids some of the drawbacks of the hotshot
- profiler and provides a bit more information than the other two profilers.
- Based on "lsprof" (patch #1212837).
-
-- Bug #1266283: The new function "lexists" is now in os.path.__all__.
-
-- Bug #981530: Fix UnboundLocalError in shutil.rmtree(). This affects
- the documented behavior: the function passed to the onerror()
- handler can now also be os.listdir.
-
-- Bug #754449: threading.Thread objects no longer mask exceptions raised during
- interpreter shutdown with another exception from attempting to handle the
- original exception.
-
-- Added decimal.py per PEP 327.
-
-- Bug #981299: rsync is now a recognized protocol in urlparse that uses a
- "netloc" portion of a URL.
-
-- Bug #919012: shutil.move() will not try to move a directory into itself.
- Thanks Johannes Gijsbers.
-
-- Bug #934282: pydoc.stripid() is now case-insensitive. Thanks Robin Becker.
-
-- Bug #823209: cmath.log() now takes an optional base argument so that its
- API matches math.log().
-
-- Bug #957381: distutils bdist_rpm no longer fails on recent RPM versions
- that generate a -debuginfo.rpm
-
-- os.path.devnull has been added for all supported platforms.
-
-- Fixed #877165: distutils now picks the right C++ compiler command
- on cygwin and mingw32.
-
-- urllib.urlopen().readline() now handles HTTP/0.9 correctly.
-
-- refactored site.py into functions. Also wrote regression tests for the
- module.
-
-- The distutils install command now supports the --home option and
- installation scheme for all platforms.
-
-- asyncore.loop now has a repeat count parameter that defaults to
- looping forever.
-
-- The distutils sdist command now ignores all .svn directories, in
- addition to CVS and RCS directories. .svn directories hold
- administrative files for the Subversion source control system.
-
-- Added a new module: cookielib. Automatic cookie handling for HTTP
- clients. Also, support for cookielib has been added to urllib2, so
- urllib2.urlopen() can transparently handle cookies.
-
-- stringprep.py now uses built-in set() instead of sets.Set().
-
-- Bug #876278: Unbounded recursion in modulefinder
-
-- Bug #780300: Swap public and system ID in LexicalHandler.startDTD.
- Applications relying on the wrong order need to be corrected.
-
-- Bug #926075: Fixed a bug that returns a wrong pattern object
- for a string or unicode object in sre.compile() when a different
- type pattern with the same value exists.
-
-- Added countcallers arg to trace.Trace class (--trackcalls command line arg
- when run from the command prompt).
-
-- Fixed a caching bug in platform.platform() where the argument of 'terse' was
- not taken into consideration when caching value.
-
-- Added two new command-line arguments for profile (output file and
- default sort).
-
-- Added global runctx function to profile module
-
-- Add hlist missing entryconfigure and entrycget methods.
-
-- The ptcp154 codec was added for Kazakh character set support.
-
-- Support non-anonymous ftp URLs in urllib2.
-
-- The encodings package will now apply codec name aliases
- first before starting to try the import of the codec module.
- This simplifies overriding built-in codecs with external
- packages, e.g. the included CJK codecs with the JapaneseCodecs
- package, by adjusting the aliases dictionary in encodings.aliases
- accordingly.
-
-- base64 now supports RFC 3548 Base16, Base32, and Base64 encoding and
- decoding standards.
-
-- urllib2 now supports processors. A processor is a handler that
- implements an xxx_request or xxx_response method. These methods are
- called for all requests.
-
-- distutils compilers now compile source files in the same order as
- they are passed to the compiler.
-
-- pprint.pprint() and pprint.pformat() now have additional parameters
- indent, width and depth.
-
-- Patch #750542: pprint now will pretty print subclasses of list, tuple
- and dict too, as long as they don't overwrite __repr__().
-
-- Bug #848614: distutils' msvccompiler fails to find the MSVC6
- compiler because of incomplete registry entries.
-
-- httplib.HTTP.putrequest now offers to omit the implicit Accept-Encoding.
-
-- Patch #841977: modulefinder didn't find extension modules in packages
-
-- imaplib.IMAP4.thread was added.
-
-- Plugged a minor hole in tempfile.mktemp() due to the use of
- os.path.exists(), switched to using os.lstat() directly if possible.
-
-- bisect.py and heapq.py now have underlying C implementations
- for better performance.
-
-- heapq.py has two new functions, nsmallest() and nlargest().
-
-- traceback.format_exc has been added (similar to print_exc but it returns
- a string).
-
-- xmlrpclib.MultiCall has been added.
-
-- poplib.POP3_SSL has been added.
-
-- tmpfile.mkstemp now returns an absolute path even if dir is relative.
-
-- urlparse is RFC 2396 compliant.
-
-- The fieldnames argument to the csv module's DictReader constructor is now
- optional. If omitted, the first row of the file will be used as the
- list of fieldnames.
-
-- encodings.bz2_codec was added for access to bz2 compression
- using "a long string".encode('bz2')
-
-- Various improvements to unittest.py, realigned with PyUnit CVS.
-
-- dircache now passes exceptions to the caller, instead of returning
- empty lists.
-
-- The bsddb module and dbhash module now support the iterator and
- mapping protocols which make them more substitutable for dictionaries
- and shelves.
-
-- The csv module's DictReader and DictWriter classes now accept keyword
- arguments. This was an omission in the initial implementation.
-
-- The email package handles some RFC 2231 parameters with missing
- CHARSET fields better. It also includes a patch to parameter
- parsing when semicolons appear inside quotes.
-
-- sets.py now runs under Py2.2. In addition, the argument restrictions
- for most set methods (but not the operators) have been relaxed to
- allow any iterable.
-
-- _strptime.py now has a behind-the-scenes caching mechanism for the most
- recent TimeRE instance used along with the last five unique directive
- patterns. The overall module was also made more thread-safe.
-
-- random.cunifvariate() and random.stdgamma() were deprecated in Py2.3
- and removed in Py2.4.
-
-- Bug #823328: urllib2.py's HTTP Digest Auth support works again.
-
-- Patch #873597: CJK codecs are imported into rank of default codecs.
-
-Tools/Demos
------------
-
-- A hotshotmain script was added to the Tools/scripts directory that
- makes it easy to run a script under control of the hotshot profiler.
-
-- The db2pickle and pickle2db scripts can now dump/load gdbm files.
-
-- The file order on the command line of the pickle2db script was reversed.
- It is now [ picklefile ] dbfile. This provides better symmetry with
- db2pickle. The file arguments to both scripts are now source followed by
- destination in situations where both files are given.
-
-- The pydoc script will display a link to the module documentation for
- modules determined to be part of the core distribution. The documentation
- base directory defaults to http://www.python.org/doc/current/lib/ but can
- be changed by setting the PYTHONDOCS environment variable.
-
-- texcheck.py now detects double word errors.
-
-- md5sum.py mistakenly opened input files in text mode by default, a
- silent and dangerous change from previous releases. It once again
- opens input files in binary mode by default. The -t and -b flags
- remain for compatibility with the 2.3 release, but -b is the default
- now.
-
-- py-electric-colon now works when pending-delete/delete-selection mode is
- in effect
-
-- py-help-at-point is no longer bound to the F1 key - it's still bound to
- C-c C-h
-
-- Pynche was fixed to not crash when there is no ~/.pynche file and no
- -d option was given.
-
-Build
------
-
-- Bug #978645: Modules/getpath.c now builds properly in --disable-framework
- build under OS X.
-
-- Profiling using gprof is now available if Python is configured with
- --enable-profiling.
-
-- Profiling the VM using the Pentium TSC is now possible if Python
- is configured --with-tsc.
-
-- In order to find libraries, setup.py now also looks in /lib64, for use
- on AMD64.
-
-- Bug #934635: Fixed a bug where the configure script couldn't detect
- getaddrinfo() properly if the KAME stack had SCTP support.
-
-- Support for missing ANSI C header files (limits.h, stddef.h, etc) was
- removed.
-
-- Systems requiring the D4, D6 or D7 variants of pthreads are no longer
- supported (see PEP 11).
-
-- Universal newline support can no longer be disabled (see PEP 11).
-
-- Support for DGUX, SunOS 4, IRIX 4 and Minix was removed (see PEP 11).
-
-- Support for systems requiring --with-dl-dld or --with-sgi-dl was removed
- (see PEP 11).
-
-- Tests for sizeof(char) were removed since ANSI C mandates that
- sizeof(char) must be 1.
-
-C API
------
-
-- Thanks to Anthony Tuininga, the datetime module now supplies a C API
- containing type-check macros and constructors. See new docs in the
- Python/C API Reference Manual for details.
-
-- Private function _PyTime_DoubleToTimet added, to convert a Python
- timestamp (C double) to platform time_t with some out-of-bounds
- checking. Declared in new header file timefuncs.h. It would be
- good to expose some other internal timemodule.c functions there.
-
-- New public functions PyEval_EvaluateFrame and PyGen_New to expose
- generator objects.
-
-- New public functions Py_IncRef() and Py_DecRef(), exposing the
- functionality of the Py_XINCREF() and Py_XDECREF macros. Useful for
- runtime dynamic embedding of Python. See patch #938302, by Bob
- Ippolito.
-
-- Added a new macro, PySequence_Fast_ITEMS, which retrieves a fast sequence's
- underlying array of PyObject pointers. Useful for high speed looping.
-
-- Created a new method flag, METH_COEXIST, which causes a method to be loaded
- even if already defined by a slot wrapper. This allows a __contains__
- method, for example, to co-exist with a defined sq_contains slot. This
- is helpful because the PyCFunction can take advantage of optimized calls
- whenever METH_O or METH_NOARGS flags are defined.
-
-- Added a new function, PyDict_Contains(d, k) which is like
- PySequence_Contains() but is specific to dictionaries and executes
- about 10% faster.
-
-- Added three new macros: Py_RETURN_NONE, Py_RETURN_TRUE, and Py_RETURN_FALSE.
- Each return the singleton they mention after Py_INCREF()ing them.
-
-- Added a new function, PyTuple_Pack(n, ...) for constructing tuples from a
- variable length argument list of Python objects without having to invoke
- the more complex machinery of Py_BuildValue(). PyTuple_Pack(3, a, b, c)
- is equivalent to Py_BuildValue("(OOO)", a, b, c).
-
-Windows
--------
-
-- The _winreg module could segfault when reading very large registry
- values, due to unchecked alloca() calls (SF bug 851056). The fix is
- uses either PyMem_Malloc(n) or PyString_FromStringAndSize(NULL, n),
- as appropriate, followed by a size check.
-
-- file.truncate() could misbehave if the file was open for update
- (modes r+, rb+, w+, wb+), and the most recent file operation before
- the truncate() call was an input operation. SF bug 801631.
-
-
-What's New in Python 2.3 final?
-===============================
-
-*Release date: 29-Jul-2003*
-
-IDLE
-----
-
-- Bug 778400: IDLE hangs when selecting "Edit with IDLE" from explorer.
- This was unique to Windows, and was fixed by adding an -n switch to
- the command the Windows installer creates to execute "Edit with IDLE"
- context-menu actions.
-
-- IDLE displays a new message upon startup: some "personal firewall"
- kinds of programs (for example, ZoneAlarm) open a dialog of their
- own when any program opens a socket. IDLE does use sockets, talking
- on the computer's internal loopback interface. This connection is not
- visible on any external interface and no data is sent to or received
- from the Internet. So, if you get such a dialog when opening IDLE,
- asking whether to let pythonw.exe talk to address 127.0.0.1, say yes,
- and rest assured no communication external to your machine is taking
- place. If you don't allow it, IDLE won't be able to start.
-
-
-What's New in Python 2.3 release candidate 2?
-=============================================
-
-*Release date: 24-Jul-2003*
-
-Core and builtins
------------------
-
-- It is now possible to import from zipfiles containing additional
- data bytes before the zip compatible archive. Zipfiles containing a
- comment at the end are still unsupported.
-
-Extension modules
------------------
-
-- A longstanding bug in the parser module's initialization could cause
- fatal internal refcount confusion when the module got initialized more
- than once. This has been fixed.
-
-- Fixed memory leak in pyexpat; using the parser's ParseFile() method
- with open files that aren't instances of the standard file type
- caused an instance of the bound .read() method to be leaked on every
- call.
-
-- Fixed some leaks in the locale module.
-
-Library
--------
-
-- Lib/encodings/rot_13.py when used as a script, now more properly
- uses the first Python interpreter on your path.
-
-- Removed caching of TimeRE (and thus LocaleTime) in _strptime.py to
- fix a locale related bug in the test suite. Although another patch
- was needed to actually fix the problem, the cache code was not
- restored.
-
-IDLE
-----
-
-- Calltips patches.
-
-Build
------
-
-- For MacOSX, added -mno-fused-madd to BASECFLAGS to fix test_coercion
- on Panther (OSX 10.3).
-
-C API
------
-
-Windows
--------
-
-- The tempfile module could do insane imports on Windows if PYTHONCASEOK
- was set, making temp file creation impossible. Repaired.
-
-- Add a patch to workaround pthread_sigmask() bugs in Cygwin.
-
-Mac
----
-
-- Various fixes to pimp.
-
-- Scripts runs with pythonw no longer had full window manager access.
-
-- Don't force boot-disk-only install, for reasons unknown it causes
- more problems than it solves.
-
-
-What's New in Python 2.3 release candidate 1?
-=============================================
-
-*Release date: 18-Jul-2003*
-
-Core and builtins
------------------
-
-- The new function sys.getcheckinterval() returns the last value set
- by sys.setcheckinterval().
-
-- Several bugs in the symbol table phase of the compiler have been
- fixed. Errors could be lost and compilation could fail without
- reporting an error. SF patch 763201.
-
-- The interpreter is now more robust about importing the warnings
- module. In an executable generated by freeze or similar programs,
- earlier versions of 2.3 would fail if the warnings module could
- not be found on the file system. Fixes SF bug 771097.
-
-- A warning about assignments to module attributes that shadow
- builtins, present in earlier releases of 2.3, has been removed.
-
-- It is not possible to create subclasses of builtin types like str
- and tuple that define an itemsize. Earlier releases of Python 2.3
- allowed this by mistake, leading to crashes and other problems.
-
-- The thread_id is now initialized to 0 in a non-thread build. SF bug
- 770247.
-
-- SF bug 762891: "del p[key]" on proxy object no longer raises SystemError.
-
-Extension modules
------------------
-
-- weakref.proxy() can now handle "del obj[i]" for proxy objects
- defining __delitem__. Formerly, it generated a SystemError.
-
-- SSL no longer crashes the interpreter when the remote side disconnects.
-
-- On Unix the mmap module can again be used to map device files.
-
-- time.strptime now exclusively uses the Python implementation
- contained within the _strptime module.
-
-- The print slot of weakref proxy objects was removed, because it was
- not consistent with the object's repr slot.
-
-- The mmap module only checks file size for regular files, not
- character or block devices. SF patch 708374.
-
-- The cPickle Pickler garbage collection support was fixed to traverse
- the find_class attribute, if present.
-
-- There are several fixes for the bsddb3 wrapper module.
-
- bsddb3 no longer crashes if an environment is closed before a cursor
- (SF bug 763298).
-
- The DB and DBEnv set_get_returns_none function was extended to take
- a level instead of a boolean flag. The new level 2 means that in
- addition, cursor.set()/.get() methods return None instead of raising
- an exception.
-
- A typo was fixed in DBCursor.join_item(), preventing a crash.
-
-Library
--------
-
-- distutils now supports MSVC 7.1
-
-- doctest now examines all docstrings by default. Previously, it would
- skip over functions with private names (as indicated by the underscore
- naming convention). The old default created too much of a risk that
- user tests were being skipped inadvertently. Note, this change could
- break code in the unlikely case that someone had intentionally put
- failing tests in the docstrings of private functions. The breakage
- is easily fixable by specifying the old behavior when calling testmod()
- or Tester().
-
-- There were several fixes to the way dumbdbms are closed. It's vital
- that a dumbdbm database be closed properly, else the on-disk data
- and directory files can be left in mutually inconsistent states.
- dumbdbm.py's _Database.__del__() method attempted to close the
- database properly, but a shutdown race in _Database._commit() could
- prevent this from working, so that a program trusting __del__() to
- get the on-disk files in synch could be badly surprised. The race
- has been repaired. A sync() method was also added so that shelve
- can guarantee data is written to disk.
-
- The close() method can now be called more than once without complaint.
-
-- The classes in threading.py are now new-style classes. That they
- weren't before was an oversight.
-
-- The urllib2 digest authentication handlers now define the correct
- auth_header. The earlier versions would fail at runtime.
-
-- SF bug 763023: fix uncaught ZeroDivisionError in difflib ratio methods
- when there are no lines.
-
-- SF bug 763637: fix exception in Tkinter with after_cancel
- which could occur with Tk 8.4
-
-- SF bug 770601: CGIHTTPServer.py now passes the entire environment
- to child processes.
-
-- SF bug 765238: add filter to fnmatch's __all__.
-
-- SF bug 748201: make time.strptime() error messages more helpful.
-
-- SF patch 764470: Do not dump the args attribute of a Fault object in
- xmlrpclib.
-
-- SF patch 549151: urllib and urllib2 now redirect POSTs on 301
- responses.
-
-- SF patch 766650: The whichdb module was fixed to recognize dbm files
- generated by gdbm on OS/2 EMX.
-
-- SF bugs 763047 and 763052: fixes bug of timezone value being left as
- -1 when ``time.tzname[0] == time.tzname[1] and not time.daylight``
- is true when it should only when time.daylight is true.
-
-- SF bug 764548: re now allows subclasses of str and unicode to be
- used as patterns.
-
-- SF bug 763637: In Tkinter, change after_cancel() to handle tuples
- of varying sizes. Tk 8.4 returns a different number of values
- than Tk 8.3.
-
-- SF bug 763023: difflib.ratio() did not catch zero division.
-
-- The Queue module now has an __all__ attribute.
-
-Tools/Demos
------------
-
-- See Lib/idlelib/NEWS.txt for IDLE news.
-
-- SF bug 753592: webchecker/wsgui now handles user supplied directories.
-
-- The trace.py script has been removed. It is now in the standard library.
-
-Build
------
-
-- Python now compiles with -fno-strict-aliasing if possible (SF bug 766696).
-
-- The socket module compiles on IRIX 6.5.10.
-
-- An irix64 system is treated the same way as an irix6 system (SF
- patch 764560).
-
-- Several definitions were missing on FreeBSD 5.x unless the
- __BSD_VISIBLE symbol was defined. configure now defines it as
- needed.
-
-C API
------
-
-- Unicode objects now support mbcs as a built-in encoding, so the C
- API can use it without deferring to the encodings package.
-
-Windows
--------
-
-- The Windows implementation of PyThread_start_new_thread() never
- checked error returns from Windows functions correctly. As a result,
- it could claim to start a new thread even when the Microsoft
- _beginthread() function failed (due to "too many threads" -- this is
- on the order of thousands when it happens). In these cases, the
- Python exception ::
-
- thread.error: can't start new thread
-
- is raised now.
-
-- SF bug 766669: Prevent a GPF on interpreter exit when sockets are in
- use. The interpreter now calls WSACleanup() from Py_Finalize()
- instead of from DLL teardown.
-
-Mac
----
-
-- Bundlebuilder now inherits default values in the right way. It was
- previously possible for app bundles to get a type of "BNDL" instead
- of "APPL." Other improvements include, a --build-id option to
- specify the CFBundleIdentifier and using the --python option to set
- the executable in the bundle.
-
-- Fixed two bugs in MacOSX framework handling.
-
-- pythonw did not allow user interaction in 2.3rc1, this has been fixed.
-
-- Python is now compiled with -mno-fused-madd, making all tests pass
- on Panther.
-
-What's New in Python 2.3 beta 2?
-================================
-
-*Release date: 29-Jun-2003*
-
-Core and builtins
------------------
-
-- A program can now set the environment variable PYTHONINSPECT to some
- string value in Python, and cause the interpreter to enter the
- interactive prompt at program exit, as if Python had been invoked
- with the -i option.
-
-- list.index() now accepts optional start and stop arguments. Similar
- changes were made to UserList.index(). SF feature request 754014.
-
-- SF patch 751998 fixes an unwanted side effect of the previous fix
- for SF bug 742860 (the next item).
-
-- SF bug 742860: "WeakKeyDictionary __delitem__ uses iterkeys". This
- wasn't threadsafe, was very inefficient (expected time O(len(dict))
- instead of O(1)), and could raise a spurious RuntimeError if another
- thread mutated the dict during __delitem__, or if a comparison function
- mutated it. It also neglected to raise KeyError when the key wasn't
- present; didn't raise TypeError when the key wasn't of a weakly
- referencable type; and broke various more-or-less obscure dict
- invariants by using a sequence of equality comparisons over the whole
- set of dict keys instead of computing the key's hash code to narrow
- the search to those keys with the same hash code. All of these are
- considered to be bugs. A new implementation of __delitem__ repairs all
- that, but note that fixing these bugs may change visible behavior in
- code relying (whether intentionally or accidentally) on old behavior.
-
-- SF bug 734869: Fixed a compiler bug that caused a fatal error when
- compiling a list comprehension that contained another list comprehension
- embedded in a lambda expression.
-
-- SF bug 705231: builtin pow() no longer lets the platform C pow()
- raise -1.0 to integer powers, because (at least) glibc gets it wrong
- in some cases. The result should be -1.0 if the power is odd and 1.0
- if the power is even, and any float with a sufficiently large exponent
- is (mathematically) an exact even integer.
-
-- SF bug 759227: A new-style class that implements __nonzero__() must
- return a bool or int (but not an int subclass) from that method. This
- matches the restriction on classic classes.
-
-- The encoding attribute has been added for file objects, and set to
- the terminal encoding on Unix and Windows.
-
-- The softspace attribute of file objects became read-only by oversight.
- It's writable again.
-
-- Reverted a 2.3 beta 1 change to iterators for subclasses of list and
- tuple. By default, the iterators now access data elements directly
- instead of going through __getitem__. If __getitem__ access is
- preferred, then __iter__ can be overridden.
-
-- SF bug 735247: The staticmethod and super types participate in
- garbage collection. Before this change, it was possible for leaks to
- occur in functions with non-global free variables that used these types.
-
-Extension modules
------------------
-
-- the socket module has a new exception, socket.timeout, to allow
- timeouts to be handled separately from other socket errors.
-
-- SF bug 751276: cPickle has fixed to propagate exceptions raised in
- user code. In earlier versions, cPickle caught and ignored any
- exception when it performed operations that it expected to raise
- specific exceptions like AttributeError.
-
-- cPickle Pickler and Unpickler objects now participate in garbage
- collection.
-
-- mimetools.choose_boundary() could return duplicate strings at times,
- especially likely on Windows. The strings returned are now guaranteed
- unique within a single program run.
-
-- thread.interrupt_main() raises KeyboardInterrupt in the main thread.
- dummy_thread has also been modified to try to simulate the behavior.
-
-- array.array.insert() now treats negative indices as being relative
- to the end of the array, just like list.insert() does. (SF bug #739313)
-
-- The datetime module classes datetime, time, and timedelta are now
- properly subclassable.
-
-- _tkinter.{get|set}busywaitinterval was added.
-
-- itertools.islice() now accepts stop=None as documented.
- Fixes SF bug #730685.
-
-- the bsddb185 module is built in one restricted instance -
- /usr/include/db.h exists and defines HASHVERSION to be 2. This is true
- for many BSD-derived systems.
-
-
-Library
--------
-
-- Some happy doctest extensions from Jim Fulton have been added to
- doctest.py. These are already being used in Zope3. The two
- primary ones:
-
- doctest.debug(module, name) extracts the doctests from the named object
- in the given module, puts them in a temp file, and starts pdb running
- on that file. This is great when a doctest fails.
-
- doctest.DocTestSuite(module=None) returns a synthesized unittest
- TestSuite instance, to be run by the unittest framework, which
- runs all the doctests in the module. This allows writing tests in
- doctest style (which can be clearer and shorter than writing tests
- in unittest style), without losing unittest's powerful testing
- framework features (which doctest lacks).
-
-- For compatibility with doctests created before 2.3, if an expected
- output block consists solely of "1" and the actual output block
- consists solely of "True", it's accepted as a match; similarly
- for "0" and "False". This is quite un-doctest-like, but is practical.
- The behavior can be disabled by passing the new doctest module
- constant DONT_ACCEPT_TRUE_FOR_1 to the new optionflags optional
- argument.
-
-- ZipFile.testzip() now only traps BadZipfile exceptions. Previously,
- a bare except caught to much and reported all errors as a problem
- in the archive.
-
-- The logging module now has a new function, makeLogRecord() making
- LogHandler easier to interact with DatagramHandler and SocketHandler.
-
-- The cgitb module has been extended to support plain text display (SF patch
- 569574).
-
-- A brand new version of IDLE (from the IDLEfork project at
- SourceForge) is now included as Lib/idlelib. The old Tools/idle is
- no more.
-
-- Added a new module: trace (documentation missing). This module used
- to be distributed in Tools/scripts. It uses sys.settrace() to trace
- code execution -- either function calls or individual lines. It can
- generate tracing output during execution or a post-mortem report of
- code coverage.
-
-- The threading module has new functions settrace() and setprofile()
- that cooperate with the functions of the same name in the sys
- module. A function registered with the threading module will
- be used for all threads it creates. The new trace module uses this
- to provide tracing for code running in threads.
-
-- copy.py: applied SF patch 707900, fixing bug 702858, by Steven
- Taschuk. Copying a new-style class that had a reference to itself
- didn't work. (The same thing worked fine for old-style classes.)
- Builtin functions are now treated as atomic, fixing bug #746304.
-
-- difflib.py has two new functions: context_diff() and unified_diff().
-
-- More fixes to urllib (SF 549151): (a) When redirecting, always use
- GET. This is common practice and more-or-less sanctioned by the
- HTTP standard. (b) Add a handler for 307 redirection, which becomes
- an error for POST, but a regular redirect for GET and HEAD
-
-- Added optional 'onerror' argument to os.walk(), to control error
- handling.
-
-- inspect.is{method|data}descriptor was added, to allow pydoc display
- __doc__ of data descriptors.
-
-- Fixed socket speed loss caused by use of the _socketobject wrapper class
- in socket.py.
-
-- timeit.py now checks the current directory for imports.
-
-- urllib2.py now knows how to order proxy classes, so the user doesn't
- have to insert it in front of other classes, nor do dirty tricks like
- inserting a "dummy" HTTPHandler after a ProxyHandler when building an
- opener with proxy support.
-
-- Iterators have been added for dbm keys.
-
-- random.Random objects can now be pickled.
-
-Tools/Demos
------------
-
-- pydoc now offers help on keywords and topics.
-
-- Tools/idle is gone; long live Lib/idlelib.
-
-- diff.py prints file diffs in context, unified, or ndiff formats,
- providing a command line interface to difflib.py.
-
-- texcheck.py is a new script for making a rough validation of Python LaTeX
- files.
-
-Build
------
-
-- Setting DESTDIR during 'make install' now allows specifying a
- different root directory.
-
-C API
------
-
-- PyType_Ready(): If a type declares that it participates in gc
- (Py_TPFLAGS_HAVE_GC), and its base class does not, and its base class's
- tp_free slot is the default _PyObject_Del, and type does not define
- a tp_free slot itself, _PyObject_GC_Del is assigned to type->tp_free.
- Previously _PyObject_Del was inherited, which could at best lead to a
- segfault. In addition, if even after this magic the type's tp_free
- slot is _PyObject_Del or NULL, and the type is a base type
- (Py_TPFLAGS_BASETYPE), TypeError is raised: since the type is a base
- type, its dealloc function must call type->tp_free, and since the type
- is gc'able, tp_free must not be NULL or _PyObject_Del.
-
-- PyThreadState_SetAsyncExc(): A new API (deliberately accessible only
- from C) to interrupt a thread by sending it an exception. It is
- intentional that you have to write your own C extension to call it
- from Python.
-
-
-New platforms
--------------
-
-None this time.
-
-Tests
------
-
-- test_imp rewritten so that it doesn't raise RuntimeError if run as a
- side effect of being imported ("import test.autotest").
-
-Windows
--------
-
-- The Windows installer ships with Tcl/Tk 8.4.3 (upgraded from 8.4.1).
-
-- The installer always suggested that Python be installed on the C:
- drive, due to a hardcoded "C:" generated by the Wise installation
- wizard. People with machines where C: is not the system drive
- usually want Python installed on whichever drive is their system drive
- instead. We removed the hardcoded "C:", and two testers on machines
- where C: is not the system drive report that the installer now
- suggests their system drive. Note that you can always select the
- directory you want in the "Select Destination Directory" dialog --
- that's what it's for.
-
-Mac
----
-
-- There's a new module called "autoGIL", which offers a mechanism to
- automatically release the Global Interpreter Lock when an event loop
- goes to sleep, allowing other threads to run. It's currently only
- supported on OSX, in the Mach-O version.
-- The OSA modules now allow direct access to properties of the
- toplevel application class (in AppleScript terminology).
-- The Package Manager can now update itself.
-
-SourceForge Bugs and Patches Applied
-------------------------------------
-
-430160, 471893, 501716, 542562, 549151, 569574, 595837, 596434,
-598163, 604210, 604716, 610332, 612627, 614770, 620190, 621891,
-622042, 639139, 640236, 644345, 649742, 649742, 658233, 660022,
-661318, 661676, 662807, 662923, 666219, 672855, 678325, 682347,
-683486, 684981, 685773, 686254, 692776, 692959, 693094, 696777,
-697989, 700827, 703666, 708495, 708604, 708901, 710733, 711902,
-713722, 715782, 718286, 719359, 719367, 723136, 723831, 723962,
-724588, 724767, 724767, 725942, 726150, 726446, 726869, 727051,
-727719, 727719, 727805, 728277, 728563, 728656, 729096, 729103,
-729293, 729297, 729300, 729317, 729395, 729622, 729817, 730170,
-730296, 730594, 730685, 730826, 730963, 731209, 731403, 731504,
-731514, 731626, 731635, 731643, 731644, 731644, 731689, 732124,
-732143, 732234, 732284, 732284, 732479, 732761, 732783, 732951,
-733667, 733781, 734118, 734231, 734869, 735051, 735293, 735527,
-735613, 735694, 736962, 736962, 737970, 738066, 739313, 740055,
-740234, 740301, 741806, 742126, 742741, 742860, 742860, 742911,
-744041, 744104, 744238, 744687, 744877, 745055, 745478, 745525,
-745620, 746012, 746304, 746366, 746801, 746953, 747348, 747667,
-747954, 748846, 748849, 748973, 748975, 749191, 749210, 749759,
-749831, 749911, 750008, 750092, 750542, 750595, 751038, 751107,
-751276, 751451, 751916, 751941, 751956, 751998, 752671, 753451,
-753602, 753617, 753845, 753925, 754014, 754340, 754447, 755031,
-755087, 755147, 755245, 755683, 755987, 756032, 756996, 757058,
-757229, 757818, 757821, 757822, 758112, 758910, 759227, 759889,
-760257, 760703, 760792, 761104, 761337, 761519, 761830, 762455
-
-
-What's New in Python 2.3 beta 1?
-================================
-
-*Release date: 25-Apr-2003*
-
-Core and builtins
------------------
-
-- New format codes B, H, I, k and K have been implemented for
- PyArg_ParseTuple and PyBuild_Value.
-
-- New builtin function sum(seq, start=0) returns the sum of all the
- items in iterable object seq, plus start (items are normally numbers,
- and cannot be strings).
-
-- bool() called without arguments now returns False rather than
- raising an exception. This is consistent with calling the
- constructors for the other builtin types -- called without argument
- they all return the false value of that type. (SF patch #724135)
-
-- In support of PEP 269 (making the pgen parser generator accessible
- from Python), some changes to the pgen code structure were made; a
- few files that used to be linked only with pgen are now linked with
- Python itself.
-
-- The repr() of a weakref object now shows the __name__ attribute of
- the referenced object, if it has one.
-
-- super() no longer ignores data descriptors, except __class__. See
- the thread started at
- http://mail.python.org/pipermail/python-dev/2003-April/034338.html
-
-- list.insert(i, x) now interprets negative i as it would be
- interpreted by slicing, so negative values count from the end of the
- list. This was the only place where such an interpretation was not
- placed on a list index.
-
-- range() now works even if the arguments are longs with magnitude
- larger than sys.maxint, as long as the total length of the sequence
- fits. E.g., range(2**100, 2**101, 2**100) is the following list:
- [1267650600228229401496703205376L]. (SF patch #707427.)
-
-- Some horridly obscure problems were fixed involving interaction
- between garbage collection and old-style classes with "ambitious"
- getattr hooks. If an old-style instance didn't have a __del__ method,
- but did have a __getattr__ hook, and the instance became reachable
- only from an unreachable cycle, and the hook resurrected or deleted
- unreachable objects when asked to resolve "__del__", anything up to
- a segfault could happen. That's been repaired.
-
-- dict.pop now takes an optional argument specifying a default
- value to return if the key is not in the dict. If a default is not
- given and the key is not found, a KeyError will still be raised.
- Parallel changes were made to UserDict.UserDict and UserDict.DictMixin.
- [SF patch #693753] (contributed by Michael Stone.)
-
-- sys.getfilesystemencoding() was added to expose
- Py_FileSystemDefaultEncoding.
-
-- New function sys.exc_clear() clears the current exception. This is
- rarely needed, but can sometimes be useful to release objects
- referenced by the traceback held in sys.exc_info()[2]. (SF patch
- #693195.)
-
-- On 64-bit systems, a dictionary could contain duplicate long/int keys
- if the key value was larger than 2**32. See SF bug #689659.
-
-- Fixed SF bug #663074. The codec system was using global static
- variables to store internal data. As a result, any attempts to use the
- unicode system with multiple active interpreters, or successive
- interpreter executions, would fail.
-
-- "%c" % u"a" now returns a unicode string instead of raising a
- TypeError. u"%c" % 0xffffffff now raises a OverflowError instead
- of a ValueError to be consistent with "%c" % 256. See SF patch #710127.
-
-Extension modules
------------------
-
-- The socket module now provides the functions inet_pton and inet_ntop
- for converting between string and packed representation of IP
- addresses. There is also a new module variable, has_ipv6, which is
- True iff the current Python has IPv6 support. See SF patch #658327.
-
-- Tkinter wrappers around Tcl variables now pass objects directly
- to Tcl, instead of first converting them to strings.
-
-- The .*? pattern in the re module is now special-cased to avoid the
- recursion limit. (SF patch #720991 -- many thanks to Gary Herron
- and Greg Chapman.)
-
-- New function sys.call_tracing() allows pdb to debug code
- recursively.
-
-- New function gc.get_referents(obj) returns a list of objects
- directly referenced by obj. In effect, it exposes what the object's
- tp_traverse slot does, and can be helpful when debugging memory
- leaks.
-
-- The iconv module has been removed from this release.
-
-- The platform-independent routines for packing floats in IEEE formats
- (struct.pack's <f, >f, <d, and >d codes; pickle and cPickle's protocol 1
- pickling of floats) ignored that rounding can cause a carry to
- propagate. The worst consequence was that, in rare cases, <f and >f
- could produce strings that, when unpacked again, were a factor of 2
- away from the original float. This has been fixed. See SF bug
- #705836.
-
-- New function time.tzset() provides access to the C library tzset()
- function, if supported. (SF patch #675422.)
-
-- Using createfilehandler, deletefilehandler, createtimerhandler functions
- on Tkinter.tkinter (_tkinter module) no longer crashes the interpreter.
- See SF bug #692416.
-
-- Modified the fcntl.ioctl() function to allow modification of a passed
- mutable buffer (for details see the reference documentation).
-
-- Made user requested changes to the itertools module.
- Subsumed the times() function into repeat().
- Added chain() and cycle().
-
-- The rotor module is now deprecated; the encryption algorithm it uses
- is not believed to be secure, and including crypto code with Python
- has implications for exporting and importing it in various countries.
-
-- The socket module now always uses the _socketobject wrapper class, even on
- platforms which have dup(2). The makefile() method is built directly
- on top of the socket without duplicating the file descriptor, allowing
- timeouts to work properly.
-
-Library
--------
-
-- New generator function os.walk() is an easy-to-use alternative to
- os.path.walk(). See os module docs for details. os.path.walk()
- isn't deprecated at this time, but may become deprecated in a
- future release.
-
-- Added new module "platform" which provides a wide range of tools
- for querying platform dependent features.
-
-- netrc now allows ASCII punctuation characters in passwords.
-
-- shelve now supports the optional writeback argument, and exposes
- pickle protocol versions.
-
-- Several methods of nntplib.NNTP have grown an optional file argument
- which specifies a file where to divert the command's output
- (already supported by the body() method). (SF patch #720468)
-
-- The self-documenting XML server library DocXMLRPCServer was added.
-
-- Support for internationalized domain names has been added through
- the 'idna' and 'punycode' encodings, the 'stringprep' module, the
- 'mkstringprep' tool, and enhancements to the socket and httplib
- modules.
-
-- htmlentitydefs has two new dictionaries: name2codepoint maps
- HTML entity names to Unicode codepoints (as integers).
- codepoint2name is the reverse mapping. See SF patch #722017.
-
-- pdb has a new command, "debug", which lets you step through
- arbitrary code from the debugger's (pdb) prompt.
-
-- unittest.failUnlessEqual and its equivalent unittest.assertEqual now
- return 'not a == b' rather than 'a != b'. This gives the desired
- result for classes that define __eq__ without defining __ne__.
-
-- sgmllib now supports SGML marked sections, in particular the
- MS Office extensions.
-
-- The urllib module now offers support for the iterator protocol.
- SF patch 698520 contributed by Brett Cannon.
-
-- New module timeit provides a simple framework for timing the
- execution speed of expressions and statements.
-
-- sets.Set objects now support mixed-type __eq__ and __ne__, instead
- of raising TypeError. If x is a Set object and y is a non-Set object,
- x == y is False, and x != y is True. This is akin to the change made
- for mixed-type comparisons of datetime objects in 2.3a2; more info
- about the rationale is in the NEWS entry for that. See also SF bug
- report <http://www.python.org/sf/693121>.
-
-- On Unix platforms, if os.listdir() is called with a Unicode argument,
- it now returns Unicode strings. (This behavior was added earlier
- to the Windows NT/2k/XP version of os.listdir().)
-
-- Distutils: both 'py_modules' and 'packages' keywords can now be specified
- in core.setup(). Previously you could supply one or the other, but
- not both of them. (SF patch #695090 from Bernhard Herzog)
-
-- New csv package makes it easy to read/write CSV files.
-
-- Module shlex has been extended to allow posix-like shell parsings,
- including a split() function for easy spliting of quoted strings and
- commands. An iterator interface was also implemented.
-
-Tools/Demos
------------
-
-- New script combinerefs.py helps analyze new PYTHONDUMPREFS output.
- See the module docstring for details.
-
-Build
------
-
-- Fix problem building on OSF1 because the compiler only accepted
- preprocessor directives that start in column 1. (SF bug #691793.)
-
-C API
------
-
-- Added PyGC_Collect(), equivalent to calling gc.collect().
-
-- PyThreadState_GetDict() was changed not to raise an exception or
- issue a fatal error when no current thread state is available. This
- makes it possible to print dictionaries when no thread is active.
-
-- LONG_LONG was renamed to PY_LONG_LONG. Extensions that use this and
- need compatibility with previous versions can use this:
-
- #ifndef PY_LONG_LONG
- #define PY_LONG_LONG LONG_LONG
- #endif
-
-- Added PyObject_SelfIter() to fill the tp_iter slot for the
- typical case where the method returns its self argument.
-
-- The extended type structure used for heap types (new-style
- classes defined by Python code using a class statement) is now
- exported from object.h as PyHeapTypeObject. (SF patch #696193.)
-
-New platforms
--------------
-
-None this time.
-
-Tests
------
-
-- test_timeout now requires -u network to be passed to regrtest to run.
- See SF bug #692988.
-
-Windows
--------
-
-- os.fsync() now exists on Windows, and calls the Microsoft _commit()
- function.
-
-- New function winsound.MessageBeep() wraps the Win32 API
- MessageBeep().
-
-Mac
----
-
-- os.listdir() now returns Unicode strings on MacOS X when called with
- a Unicode argument. See the general news item under "Library".
-
-- A new method MacOS.WMAvailable() returns true if it is safe to access
- the window manager, false otherwise.
-
-- EasyDialogs dialogs are now movable-modal, and if the application is
- currently in the background they will ask to be moved to the foreground
- before displaying.
-
-- OSA Scripting support has improved a lot, and gensuitemodule.py can now
- be used by mere mortals. The documentation is now also more or less
- complete.
-
-- The IDE (in a framework build) now includes introductory documentation
- in Apple Help Viewer format.
-
-
-What's New in Python 2.3 alpha 2?
-=================================
-
-*Release date: 19-Feb-2003*
-
-Core and builtins
------------------
-
-- Negative positions returned from PEP 293 error callbacks are now
- treated as being relative to the end of the input string. Positions
- that are out of bounds raise an IndexError.
-
-- sys.path[0] (the directory from which the script is loaded) is now
- turned into an absolute pathname, unless it is the empty string.
- (SF patch #664376.)
-
-- Finally fixed the bug in compile() and exec where a string ending
- with an indented code block but no newline would raise SyntaxError.
- This would have been a four-line change in parsetok.c... Except
- codeop.py depends on this behavior, so a compilation flag had to be
- invented that causes the tokenizer to revert to the old behavior;
- this required extra changes to 2 .h files, 2 .c files, and 2 .py
- files. (Fixes SF bug #501622.)
-
-- If a new-style class defines neither __new__ nor __init__, its
- constructor would ignore all arguments. This is changed now: the
- constructor refuses arguments in this case. This might break code
- that worked under Python 2.2. The simplest fix is to add a no-op
- __init__: ``def __init__(self, *args, **kw): pass``.
-
-- Through a bytecode optimizer bug (and I bet you didn't even know
- Python *had* a bytecode optimizer :-), "unsigned" hex/oct constants
- with a leading minus sign would come out with the wrong sign.
- ("Unsigned" hex/oct constants are those with a face value in the
- range sys.maxint+1 through sys.maxint*2+1, inclusive; these have
- always been interpreted as negative numbers through sign folding.)
- E.g. 0xffffffff is -1, and -(0xffffffff) is 1, but -0xffffffff would
- come out as -4294967295. This was the case in Python 2.2 through
- 2.2.2 and 2.3a1, and in Python 2.4 it will once again have that
- value, but according to PEP 237 it really needs to be 1 now. This
- will be backported to Python 2.2.3 a well. (SF #660455)
-
-- int(s, base) sometimes sign-folds hex and oct constants; it only
- does this when base is 0 and s.strip() starts with a '0'. When the
- sign is actually folded, as in int("0xffffffff", 0) on a 32-bit
- machine, which returns -1, a FutureWarning is now issued; in Python
- 2.4, this will return 4294967295L, as do int("+0xffffffff", 0) and
- int("0xffffffff", 16) right now. (PEP 347)
-
-- super(X, x): x may now be a proxy for an X instance, i.e.
- issubclass(x.__class__, X) but not issubclass(type(x), X).
-
-- isinstance(x, X): if X is a new-style class, this is now equivalent
- to issubclass(type(x), X) or issubclass(x.__class__, X). Previously
- only type(x) was tested. (For classic classes this was already the
- case.)
-
-- compile(), eval() and the exec statement now fully support source code
- passed as unicode strings.
-
-- int subclasses can be initialized with longs if the value fits in an int.
- See SF bug #683467.
-
-- long(string, base) takes time linear in len(string) when base is a power
- of 2 now. It used to take time quadratic in len(string).
-
-- filter returns now Unicode results for Unicode arguments.
-
-- raw_input can now return Unicode objects.
-
-- List objects' sort() method now accepts None as the comparison function.
- Passing None is semantically identical to calling sort() with no
- arguments.
-
-- Fixed crash when printing a subclass of str and __str__ returned self.
- See SF bug #667147.
-
-- Fixed an invalid RuntimeWarning and an undetected error when trying
- to convert a long integer into a float which couldn't fit.
- See SF bug #676155.
-
-- Function objects now have a __module__ attribute that is bound to
- the name of the module in which the function was defined. This
- applies for C functions and methods as well as functions and methods
- defined in Python. This attribute is used by pickle.whichmodule(),
- which changes the behavior of whichmodule slightly. In Python 2.2
- whichmodule() returns "__main__" for functions that are not defined
- at the top-level of a module (examples: methods, nested functions).
- Now whichmodule() will return the proper module name.
-
-Extension modules
------------------
-
-- operator.isNumberType() now checks that the object has a nb_int or
- nb_float slot, rather than simply checking whether it has a non-NULL
- tp_as_number pointer.
-
-- The imp module now has ways to acquire and release the "import
- lock": imp.acquire_lock() and imp.release_lock(). Note: this is a
- reentrant lock, so releasing the lock only truly releases it when
- this is the last release_lock() call. You can check with
- imp.lock_held(). (SF bug #580952 and patch #683257.)
-
-- Change to cPickle to match pickle.py (see below and PEP 307).
-
-- Fix some bugs in the parser module. SF bug #678518.
-
-- Thanks to Scott David Daniels, a subtle bug in how the zlib
- extension implemented flush() was fixed. Scott also rewrote the
- zlib test suite using the unittest module. (SF bug #640230 and
- patch #678531.)
-
-- Added an itertools module containing high speed, memory efficient
- looping constructs inspired by tools from Haskell and SML.
-
-- The SSL module now handles sockets with a timeout set correctly (SF
- patch #675750, fixing SF bug #675552).
-
-- os/posixmodule has grown the sysexits.h constants (EX_OK and friends).
-
-- Fixed broken threadstate swap in readline that could cause fatal
- errors when a readline hook was being invoked while a background
- thread was active. (SF bugs #660476 and #513033.)
-
-- fcntl now exposes the strops.h I_* constants.
-
-- Fix a crash on Solaris that occurred when calling close() on
- an mmap'ed file which was already closed. (SF patch #665913)
-
-- Fixed several serious bugs in the zipimport implementation.
-
-- datetime changes:
-
- The date class is now properly subclassable. (SF bug #720908)
-
- The datetime and datetimetz classes have been collapsed into a single
- datetime class, and likewise the time and timetz classes into a single
- time class. Previously, a datetimetz object with tzinfo=None acted
- exactly like a datetime object, and similarly for timetz. This wasn't
- enough of a difference to justify distinct classes, and life is simpler
- now.
-
- today() and now() now round system timestamps to the closest
- microsecond <http://www.python.org/sf/661086>. This repairs an
- irritation most likely seen on Windows systems.
-
- In dt.astimezone(tz), if tz.utcoffset(dt) returns a duration,
- ValueError is raised if tz.dst(dt) returns None (2.3a1 treated it
- as 0 instead, but a tzinfo subclass wishing to participate in
- time zone conversion has to take a stand on whether it supports
- DST; if you don't care about DST, then code dst() to return 0 minutes,
- meaning that DST is never in effect).
-
- The tzinfo methods utcoffset() and dst() must return a timedelta object
- (or None) now. In 2.3a1 they could also return an int or long, but that
- was an unhelpfully redundant leftover from an earlier version wherein
- they couldn't return a timedelta. TOOWTDI.
-
- The example tzinfo class for local time had a bug. It was replaced
- by a later example coded by Guido.
-
- datetime.astimezone(tz) no longer raises an exception when the
- input datetime has no UTC equivalent in tz. For typical "hybrid" time
- zones (a single tzinfo subclass modeling both standard and daylight
- time), this case can arise one hour per year, at the hour daylight time
- ends. See new docs for details. In short, the new behavior mimics
- the local wall clock's behavior of repeating an hour in local time.
-
- dt.astimezone() can no longer be used to convert between naive and aware
- datetime objects. If you merely want to attach, or remove, a tzinfo
- object, without any conversion of date and time members, use
- dt.replace(tzinfo=whatever) instead, where "whatever" is None or a
- tzinfo subclass instance.
-
- A new method tzinfo.fromutc(dt) can be overridden in tzinfo subclasses
- to give complete control over how a UTC time is to be converted to
- a local time. The default astimezone() implementation calls fromutc()
- as its last step, so a tzinfo subclass can affect that too by overriding
- fromutc(). It's expected that the default fromutc() implementation will
- be suitable as-is for "almost all" time zone subclasses, but the
- creativity of political time zone fiddling appears unbounded -- fromutc()
- allows the highly motivated to emulate any scheme expressible in Python.
-
- datetime.now(): The optional tzinfo argument was undocumented (that's
- repaired), and its name was changed to tz ("tzinfo" is overloaded enough
- already). With a tz argument, now(tz) used to return the local date
- and time, and attach tz to it, without any conversion of date and time
- members. This was less than useful. Now now(tz) returns the current
- date and time as local time in tz's time zone, akin to ::
-
- tz.fromutc(datetime.utcnow().replace(tzinfo=utc))
-
- where "utc" is an instance of a tzinfo subclass modeling UTC. Without
- a tz argument, now() continues to return the current local date and time,
- as a naive datetime object.
-
- datetime.fromtimestamp(): Like datetime.now() above, this had less than
- useful behavior when the optional tinzo argument was specified. See
- also SF bug report <http://www.python.org/sf/660872>.
-
- date and datetime comparison: In order to prevent comparison from
- falling back to the default compare-object-addresses strategy, these
- raised TypeError whenever they didn't understand the other object type.
- They still do, except when the other object has a "timetuple" attribute,
- in which case they return NotImplemented now. This gives other
- datetime objects (e.g., mxDateTime) a chance to intercept the
- comparison.
-
- date, time, datetime and timedelta comparison: When the exception
- for mixed-type comparisons in the last paragraph doesn't apply, if
- the comparison is == then False is returned, and if the comparison is
- != then True is returned. Because dict lookup and the "in" operator
- only invoke __eq__, this allows, for example, ::
-
- if some_datetime in some_sequence:
-
- and ::
-
- some_dict[some_timedelta] = whatever
-
- to work as expected, without raising TypeError just because the
- sequence is heterogeneous, or the dict has mixed-type keys. [This
- seems like a good idea to implement for all mixed-type comparisons
- that don't want to allow falling back to address comparison.]
-
- The constructors building a datetime from a timestamp could raise
- ValueError if the platform C localtime()/gmtime() inserted "leap
- seconds". Leap seconds are ignored now. On such platforms, it's
- possible to have timestamps that differ by a second, yet where
- datetimes constructed from them are equal.
-
- The pickle format of date, time and datetime objects has changed
- completely. The undocumented pickler and unpickler functions no
- longer exist. The undocumented __setstate__() and __getstate__()
- methods no longer exist either.
-
-Library
--------
-
-- The logging module was updated slightly; the WARN level was renamed
- to WARNING, and the matching function/method warn() to warning().
-
-- The pickle and cPickle modules were updated with a new pickling
- protocol (documented by pickletools.py, see below) and several
- extensions to the pickle customization API (__reduce__, __setstate__
- etc.). The copy module now uses more of the pickle customization
- API to copy objects that don't implement __copy__ or __deepcopy__.
- See PEP 307 for details.
-
-- The distutils "register" command now uses http://www.python.org/pypi
- as the default repository. (See PEP 301.)
-
-- the platform dependent path related variables sep, altsep, extsep,
- pathsep, curdir, pardir and defpath are now defined in the platform
- dependent path modules (e.g. ntpath.py) rather than os.py, so these
- variables are now available via os.path. They continue to be
- available from the os module.
- (see <http://www.python.org/sf/680789>).
-
-- array.array was added to the types repr.py knows about (see
- <http://www.python.org/sf/680789>).
-
-- The new pickletools.py contains lots of documentation about pickle
- internals, and supplies some helpers for working with pickles, such as
- a symbolic pickle disassembler.
-
-- Xmlrpclib.py now supports the builtin boolean type.
-
-- py_compile has a new 'doraise' flag and a new PyCompileError
- exception.
-
-- SimpleXMLRPCServer now supports CGI through the CGIXMLRPCRequestHandler
- class.
-
-- The sets module now raises TypeError in __cmp__, to clarify that
- sets are not intended to be three-way-compared; the comparison
- operators are overloaded as subset/superset tests.
-
-- Bastion.py and rexec.py are disabled. These modules are not safe in
- Python 2.2. or 2.3.
-
-- realpath is now exported when doing ``from poxixpath import *``.
- It is also exported for ntpath, macpath, and os2emxpath.
- See SF bug #659228.
-
-- New module tarfile from Lars Gustäbel provides a comprehensive interface
- to tar archive files with transparent gzip and bzip2 compression.
- See SF patch #651082.
-
-- urlparse can now parse imap:// URLs. See SF feature request #618024.
-
-- Tkinter.Canvas.scan_dragto() provides an optional parameter to support
- the gain value which is passed to Tk. SF bug# 602259.
-
-- Fix logging.handlers.SysLogHandler protocol when using UNIX domain sockets.
- See SF patch #642974.
-
-- The dospath module was deleted. Use the ntpath module when manipulating
- DOS paths from other platforms.
-
-Tools/Demos
------------
-
-- Two new scripts (db2pickle.py and pickle2db.py) were added to the
- Tools/scripts directory to facilitate conversion from the old bsddb module
- to the new one. While the user-visible API of the new module is
- compatible with the old one, it's likely that the version of the
- underlying database library has changed. To convert from the old library,
- run the db2pickle.py script using the old version of Python to convert it
- to a pickle file. After upgrading Python, run the pickle2db.py script
- using the new version of Python to reconstitute your database. For
- example:
-
- % python2.2 db2pickle.py -h some.db > some.pickle
- % python2.3 pickle2db.py -h some.db.new < some.pickle
-
- Run the scripts without any args to get a usage message.
-
-
-Build
------
-
-- The audio driver tests (test_ossaudiodev.py and
- test_linuxaudiodev.py) are no longer run by default. This is
- because they don't always work, depending on your hardware and
- software. To run these tests, you must use an invocation like ::
-
- ./python Lib/test/regrtest.py -u audio test_ossaudiodev
-
-- On systems which build using the configure script, compiler flags which
- used to be lumped together using the OPT flag have been split into two
- groups, OPT and BASECFLAGS. OPT is meant to carry just optimization- and
- debug-related flags like "-g" and "-O3". BASECFLAGS is meant to carry
- compiler flags that are required to get a clean compile. On some
- platforms (many Linux flavors in particular) BASECFLAGS will be empty by
- default. On others, such as Mac OS X and SCO, it will contain required
- flags. This change allows people building Python to override OPT without
- fear of clobbering compiler flags which are required to get a clean build.
-
-- On Darwin/Mac OS X platforms, /sw/lib and /sw/include are added to the
- relevant search lists in setup.py. This allows users building Python to
- take advantage of the many packages available from the fink project
- <http://fink.sf.net/>.
-
-- A new Makefile target, scriptsinstall, installs a number of useful scripts
- from the Tools/scripts directory.
-
-C API
------
-
-- PyEval_GetFrame() is now declared to return a ``PyFrameObject *``
- instead of a plain ``PyObject *``. (SF patch #686601.)
-
-- PyNumber_Check() now checks that the object has a nb_int or nb_float
- slot, rather than simply checking whether it has a non-NULL
- tp_as_number pointer.
-
-- A C type that inherits from a base type that defines tp_as_buffer
- will now inherit the tp_as_buffer pointer if it doesn't define one.
- (SF #681367)
-
-- The PyArg_Parse functions now issue a DeprecationWarning if a float
- argument is provided when an integer is specified (this affects the 'b',
- 'B', 'h', 'H', 'i', and 'l' codes). Future versions of Python will
- raise a TypeError.
-
-Tests
------
-
-- Several tests weren't being run from regrtest.py (test_timeout.py,
- test_tarfile.py, test_netrc.py, test_multifile.py,
- test_importhooks.py and test_imp.py). Now they are. (Note to
- developers: please read Lib/test/README when creating a new test, to
- make sure to do it right! All tests need to use either unittest or
- pydoc.)
-
-- Added test_posix.py, a test suite for the posix module.
-
-- Added test_hexoct.py, a test suite for hex/oct constant folding.
-
-Windows
--------
-
-- The timeout code for socket connect() didn't work right; this has
- now been fixed. test_timeout.py should pass (at least most of the
- time).
-
-- distutils' msvccompiler class now passes the preprocessor options to
- the resource compiler. See SF patch #669198.
-
-- The bsddb module now ships with Sleepycat's 4.1.25.NC, the latest
- release without strong cryptography.
-
-- sys.path[0], if it contains a directory name, is now always an
- absolute pathname. (SF patch #664376.)
-
-- The new logging package is now installed by the Windows installer. It
- wasn't in 2.3a1 due to oversight.
-
-Mac
----
-
-- There are new dialogs EasyDialogs.AskFileForOpen, AskFileForSave
- and AskFolder. The old macfs.StandardGetFile and friends are deprecated.
-
-- Most of the standard library now uses pathnames or FSRefs in preference
- of FSSpecs, and use the underlying Carbon.File and Carbon.Folder modules
- in stead of macfs. macfs will probably be deprecated in the future.
-
-- Type Carbon.File.FSCatalogInfo and supporting methods have been implemented.
- This also makes macfs.FSSpec.SetDates() work again.
-
-- There is a new module pimp, the package install manager for Python, and
- accompanying applet PackageManager. These allow you to easily download
- and install pretested extension packages either in source or binary
- form. Only in MacPython-OSX.
-
-- Applets are now built with bundlebuilder in MacPython-OSX, which should make
- them more robust and also provides a path towards BuildApplication. The
- downside of this change is that applets can no longer be run from the
- Terminal window, this will hopefully be fixed in the 2.3b1.
-
-
-What's New in Python 2.3 alpha 1?
-=================================
-
-*Release date: 31-Dec-2002*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- One can now assign to __bases__ and __name__ of new-style classes.
-
-- dict() now accepts keyword arguments so that dict(one=1, two=2)
- is the equivalent of {"one": 1, "two": 2}. Accordingly,
- the existing (but undocumented) 'items' keyword argument has
- been eliminated. This means that dict(items=someMapping) now has
- a different meaning than before.
-
-- int() now returns a long object if the argument is outside the
- integer range, so int("4" * 1000), int(1e200) and int(1L<<1000) will
- all return long objects instead of raising an OverflowError.
-
-- Assignment to __class__ is disallowed if either the old or the new
- class is a statically allocated type object (such as defined by an
- extension module). This prevents anomalies like 2.__class__ = bool.
-
-- New-style object creation and deallocation have been sped up
- significantly; they are now faster than classic instance creation
- and deallocation.
-
-- The __slots__ variable can now mention "private" names, and the
- right thing will happen (e.g. __slots__ = ["__foo"]).
-
-- The built-ins slice() and buffer() are now callable types. The
- types classobj (formerly class), code, function, instance, and
- instancemethod (formerly instance-method), which have no built-in
- names but are accessible through the types module, are now also
- callable. The type dict-proxy is renamed to dictproxy.
-
-- Cycles going through the __class__ link of a new-style instance are
- now detected by the garbage collector.
-
-- Classes using __slots__ are now properly garbage collected.
- [SF bug 519621]
-
-- Tightened the __slots__ rules: a slot name must be a valid Python
- identifier.
-
-- The constructor for the module type now requires a name argument and
- takes an optional docstring argument. Previously, this constructor
- ignored its arguments. As a consequence, deriving a class from a
- module (not from the module type) is now illegal; previously this
- created an unnamed module, just like invoking the module type did.
- [SF bug 563060]
-
-- A new type object, 'basestring', is added. This is a common base type
- for 'str' and 'unicode', and can be used instead of
- types.StringTypes, e.g. to test whether something is "a string":
- isinstance(x, basestring) is True for Unicode and 8-bit strings. This
- is an abstract base class and cannot be instantiated directly.
-
-- Changed new-style class instantiation so that when C's __new__
- method returns something that's not a C instance, its __init__ is
- not called. [SF bug #537450]
-
-- Fixed super() to work correctly with class methods. [SF bug #535444]
-
-- If you try to pickle an instance of a class that has __slots__ but
- doesn't define or override __getstate__, a TypeError is now raised.
- This is done by adding a bozo __getstate__ to the class that always
- raises TypeError. (Before, this would appear to be pickled, but the
- state of the slots would be lost.)
-
-Core and builtins
------------------
-
-- Import from zipfiles is now supported. The name of a zipfile placed
- on sys.path causes the import statement to look for importable Python
- modules (with .py, pyc and .pyo extensions) and packages inside the
- zipfile. The zipfile import follows the specification (though not
- the sample implementation) of PEP 273. The semantics of __path__ are
- compatible with those that have been implemented in Jython since
- Jython 2.1.
-
-- PEP 302 has been accepted. Although it was initially developed to
- support zipimport, it offers a new, general import hook mechanism.
- Several new variables have been added to the sys module:
- sys.meta_path, sys.path_hooks, and sys.path_importer_cache; these
- make extending the import statement much more convenient than
- overriding the __import__ built-in function. For a description of
- these, see PEP 302.
-
-- A frame object's f_lineno attribute can now be written to from a
- trace function to change which line will execute next. A command to
- exploit this from pdb has been added. [SF patch #643835]
-
-- The _codecs support module for codecs.py was turned into a builtin
- module to assure that at least the builtin codecs are available
- to the Python parser for source code decoding according to PEP 263.
-
-- issubclass now supports a tuple as the second argument, just like
- isinstance does. ``issubclass(X, (A, B))`` is equivalent to
- ``issubclass(X, A) or issubclass(X, B)``.
-
-- Thanks to Armin Rigo, the last known way to provoke a system crash
- by cleverly arranging for a comparison function to mutate a list
- during a list.sort() operation has been fixed. The effect of
- attempting to mutate a list, or even to inspect its contents or
- length, while a sort is in progress, is not defined by the language.
- The C implementation of Python 2.3 attempts to detect mutations,
- and raise ValueError if one occurs, but there's no guarantee that
- all mutations will be caught, or that any will be caught across
- releases or implementations.
-
-- Unicode file name processing for Windows (PEP 277) is implemented.
- All platforms now have an os.path.supports_unicode_filenames attribute,
- which is set to True on Windows NT/2000/XP, and False elsewhere.
-
-- Codec error handling callbacks (PEP 293) are implemented.
- Error handling in unicode.encode or str.decode can now be customized.
-
-- A subtle change to the semantics of the built-in function intern():
- interned strings are no longer immortal. You must keep a reference
- to the return value intern() around to get the benefit.
-
-- Use of 'None' as a variable, argument or attribute name now
- issues a SyntaxWarning. In the future, None may become a keyword.
-
-- SET_LINENO is gone. co_lnotab is now consulted to determine when to
- call the trace function. C code that accessed f_lineno should call
- PyCode_Addr2Line instead (f_lineno is still there, but only kept up
- to date when there is a trace function set).
-
-- There's a new warning category, FutureWarning. This is used to warn
- about a number of situations where the value or sign of an integer
- result will change in Python 2.4 as a result of PEP 237 (integer
- unification). The warnings implement stage B0 mentioned in that
- PEP. The warnings are about the following situations:
-
- - Octal and hex literals without 'L' prefix in the inclusive range
- [0x80000000..0xffffffff]; these are currently negative ints, but
- in Python 2.4 they will be positive longs with the same bit
- pattern.
-
- - Left shifts on integer values that cause the outcome to lose
- bits or have a different sign than the left operand. To be
- precise: x<<n where this currently doesn't yield the same value
- as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
-
- - Conversions from ints to string that show negative values as
- unsigned ints in the inclusive range [0x80000000..0xffffffff];
- this affects the functions hex() and oct(), and the string
- formatting codes %u, %o, %x, and %X. In Python 2.4, these will
- show signed values (e.g. hex(-1) currently returns "0xffffffff";
- in Python 2.4 it will return "-0x1").
-
-- The bits manipulated under the cover by sys.setcheckinterval() have
- been changed. Both the check interval and the ticker used to be
- per-thread values. They are now just a pair of global variables.
- In addition, the default check interval was boosted from 10 to 100
- bytecode instructions. This may have some effect on systems that
- relied on the old default value. In particular, in multi-threaded
- applications which try to be highly responsive, response time will
- increase by some (perhaps imperceptible) amount.
-
-- When multiplying very large integers, a version of the so-called
- Karatsuba algorithm is now used. This is most effective if the
- inputs have roughly the same size. If they both have about N digits,
- Karatsuba multiplication has O(N**1.58) runtime (the exponent is
- log_base_2(3)) instead of the previous O(N**2). Measured results may
- be better or worse than that, depending on platform quirks. Besides
- the O() improvement in raw instruction count, the Karatsuba algorithm
- appears to have much better cache behavior on extremely large integers
- (starting in the ballpark of a million bits). Note that this is a
- simple implementation, and there's no intent here to compete with,
- e.g., GMP. It gives a very nice speedup when it applies, but a package
- devoted to fast large-integer arithmetic should run circles around it.
-
-- u'%c' will now raise a ValueError in case the argument is an
- integer outside the valid range of Unicode code point ordinals.
-
-- The tempfile module has been overhauled for enhanced security. The
- mktemp() function is now deprecated; new, safe replacements are
- mkstemp() (for files) and mkdtemp() (for directories), and the
- higher-level functions NamedTemporaryFile() and TemporaryFile().
- Use of some global variables in this module is also deprecated; the
- new functions have keyword arguments to provide the same
- functionality. All Lib, Tools and Demo modules that used the unsafe
- interfaces have been updated to use the safe replacements. Thanks
- to Zack Weinberg!
-
-- When x is an object whose class implements __mul__ and __rmul__,
- 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
- invoke __mul__. This was due to the sequence-repeat code in the int
- type. This has been fixed now.
-
-- Previously, "str1 in str2" required str1 to be a string of length 1.
- This restriction has been relaxed to allow str1 to be a string of
- any length. Thus "'el' in 'hello world'" returns True now.
-
-- File objects are now their own iterators. For a file f, iter(f) now
- returns f (unless f is closed), and f.next() is similar to
- f.readline() when EOF is not reached; however, f.next() uses a
- readahead buffer that messes up the file position, so mixing
- f.next() and f.readline() (or other methods) doesn't work right.
- Calling f.seek() drops the readahead buffer, but other operations
- don't. It so happens that this gives a nice additional speed boost
- to "for line in file:"; the xreadlines method and corresponding
- module are now obsolete. Thanks to Oren Tirosh!
-
-- Encoding declarations (PEP 263, phase 1) have been implemented. A
- comment of the form "# -*- coding: <encodingname> -*-" in the first
- or second line of a Python source file indicates the encoding.
-
-- list.sort() has a new implementation. While cross-platform results
- may vary, and in data-dependent ways, this is much faster on many
- kinds of partially ordered lists than the previous implementation,
- and reported to be just as fast on randomly ordered lists on
- several major platforms. This sort is also stable (if A==B and A
- precedes B in the list at the start, A precedes B after the sort too),
- although the language definition does not guarantee stability. A
- potential drawback is that list.sort() may require temp space of
- len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
- for list.sort() to raise MemoryError now, even if a comparison function
- does not. See <http://www.python.org/sf/587076> for full details.
-
-- All standard iterators now ensure that, once StopIteration has been
- raised, all future calls to next() on the same iterator will also
- raise StopIteration. There used to be various counterexamples to
- this behavior, which could caused confusion or subtle program
- breakage, without any benefits. (Note that this is still an
- iterator's responsibility; the iterator framework does not enforce
- this.)
-
-- Ctrl+C handling on Windows has been made more consistent with
- other platforms. KeyboardInterrupt can now reliably be caught,
- and Ctrl+C at an interactive prompt no longer terminates the
- process under NT/2k/XP (it never did under Win9x). Ctrl+C will
- interrupt time.sleep() in the main thread, and any child processes
- created via the popen family (on win2k; we can't make win9x work
- reliably) are also interrupted (as generally happens on for Linux/Unix.)
- [SF bugs 231273, 439992 and 581232]
-
-- sys.getwindowsversion() has been added on Windows. This
- returns a tuple with information about the version of Windows
- currently running.
-
-- Slices and repetitions of buffer objects now consistently return
- a string. Formerly, strings would be returned most of the time,
- but a buffer object would be returned when the repetition count
- was one or when the slice range was all inclusive.
-
-- Unicode objects in sys.path are no longer ignored but treated
- as directory names.
-
-- Fixed string.startswith and string.endswith builtin methods
- so they accept negative indices. [SF bug 493951]
-
-- Fixed a bug with a continue inside a try block and a yield in the
- finally clause. [SF bug 567538]
-
-- Most builtin sequences now support "extended slices", i.e. slices
- with a third "stride" parameter. For example, "hello world"[::-1]
- gives "dlrow olleh".
-
-- A new warning PendingDeprecationWarning was added to provide
- direction on features which are in the process of being deprecated.
- The warning will not be printed by default. To see the pending
- deprecations, use -Walways::PendingDeprecationWarning::
- as a command line option or warnings.filterwarnings() in code.
-
-- Deprecated features of xrange objects have been removed as
- promised. The start, stop, and step attributes and the tolist()
- method no longer exist. xrange repetition and slicing have been
- removed.
-
-- New builtin function enumerate(x), from PEP 279. Example:
- enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
- The argument can be an arbitrary iterable object.
-
-- The assert statement no longer tests __debug__ at runtime. This means
- that assert statements cannot be disabled by assigning a false value
- to __debug__.
-
-- A method zfill() was added to str and unicode, that fills a numeric
- string to the left with zeros. For example,
- "+123".zfill(6) -> "+00123".
-
-- Complex numbers supported divmod() and the // and % operators, but
- these make no sense. Since this was documented, they're being
- deprecated now.
-
-- String and unicode methods lstrip(), rstrip() and strip() now take
- an optional argument that specifies the characters to strip. For
- example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
-
-- There's a new dictionary constructor (a class method of the dict
- class), dict.fromkeys(iterable, value=None). It constructs a
- dictionary with keys taken from the iterable and all values set to a
- single value. It can be used for building sets and for removing
- duplicates from sequences.
-
-- Added a new dict method pop(key). This removes and returns the
- value corresponding to key. [SF patch #539949]
-
-- A new built-in type, bool, has been added, as well as built-in
- names for its two values, True and False. Comparisons and sundry
- other operations that return a truth value have been changed to
- return a bool instead. Read PEP 285 for an explanation of why this
- is backward compatible.
-
-- Fixed two bugs reported as SF #535905: under certain conditions,
- deallocating a deeply nested structure could cause a segfault in the
- garbage collector, due to interaction with the "trashcan" code;
- access to the current frame during destruction of a local variable
- could access a pointer to freed memory.
-
-- The optional object allocator ("pymalloc") has been enabled by
- default. The recommended practice for memory allocation and
- deallocation has been streamlined. A header file is included,
- Misc/pymemcompat.h, which can be bundled with 3rd party extensions
- and lets them use the same API with Python versions from 1.5.2
- onwards.
-
-- PyErr_Display will provide file and line information for all exceptions
- that have an attribute print_file_and_line, not just SyntaxErrors.
-
-- The UTF-8 codec will now encode and decode Unicode surrogates
- correctly and without raising exceptions for unpaired ones.
-
-- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
- instead of 'r' when opening a text file for reading changes the line
- ending convention so that any of '\r', '\r\n', and '\n' is
- recognized (even mixed in one file); all three are converted to
- '\n', the standard Python line end character.
-
-- file.xreadlines() now raises a ValueError if the file is closed:
- Previously, an xreadlines object was returned which would raise
- a ValueError when the xreadlines.next() method was called.
-
-- sys.exit() inadvertently allowed more than one argument.
- An exception will now be raised if more than one argument is used.
-
-- Changed evaluation order of dictionary literals to conform to the
- general left to right evaluation order rule. Now {f1(): f2()} will
- evaluate f1 first.
-
-- Fixed bug #521782: when a file was in non-blocking mode, file.read()
- could silently lose data or wrongly throw an unknown error.
-
-- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
- slots are now always tried after trying the corresponding nb_* slots.
- This fixes a number of minor bugs (see bug #624807).
-
-- Fix problem with dynamic loading on 64-bit AIX (see bug #639945).
-
-Extension modules
------------------
-
-- Added three operators to the operator module:
- operator.pow(a,b) which is equivalent to: a**b.
- operator.is_(a,b) which is equivalent to: a is b.
- operator.is_not(a,b) which is equivalent to: a is not b.
-
-- posix.openpty now works on all systems that have /dev/ptmx.
-
-- A module zipimport exists to support importing code from zip
- archives.
-
-- The new datetime module supplies classes for manipulating dates and
- times. The basic design came from the Zope "fishbowl process", and
- favors practical commercial applications over calendar esoterica. See
-
- http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
-
-- _tkinter now returns Tcl objects, instead of strings. Objects which
- have Python equivalents are converted to Python objects, other objects
- are wrapped. This can be configured through the wantobjects method,
- or Tkinter.wantobjects.
-
-- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
- been added as the package bsddb. The traditional bsddb module is
- still available in source code, but not built automatically anymore,
- and is now named bsddb185. This supports Berkeley DB versions from
- 3.0 to 4.1. For help converting your databases from the old module (which
- probably used an obsolete version of Berkeley DB) to the new module, see
- the db2pickle.py and pickle2db.py scripts described in the Tools/Demos
- section above.
-
-- unicodedata was updated to Unicode 3.2. It supports normalization
- and names for Hangul syllables and CJK unified ideographs.
-
-- resource.getrlimit() now returns longs instead of ints.
-
-- readline now dynamically adjusts its input/output stream if
- sys.stdin/stdout changes.
-
-- The _tkinter module (and hence Tkinter) has dropped support for
- Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
- supported.
-
-- cPickle.BadPickleGet is now a class.
-
-- The time stamps in os.stat_result are floating point numbers
- after stat_float_times has been called.
-
-- If the size passed to mmap.mmap() is larger than the length of the
- file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
-
-- The xreadlines module is slated for obsolescence.
-
-- The strptime function in the time module is now always available (a
- Python implementation is used when the C library doesn't define it).
-
-- The 'new' module is no longer an extension, but a Python module that
- only exists for backwards compatibility. Its contents are no longer
- functions but callable type objects.
-
-- The bsddb.*open functions can now take 'None' as a filename.
- This will create a temporary in-memory bsddb that won't be
- written to disk.
-
-- posix.getloadavg, posix.lchown, posix.killpg, posix.mknod, and
- posix.getpgid have been added where available.
-
-- The locale module now exposes the C library's gettext interface. It
- also has a new function getpreferredencoding.
-
-- A security hole ("double free") was found in zlib-1.1.3, a popular
- third party compression library used by some Python modules. The
- hole was quickly plugged in zlib-1.1.4, and the Windows build of
- Python now ships with zlib-1.1.4.
-
-- pwd, grp, and resource return enhanced tuples now, with symbolic
- field names.
-
-- array.array is now a type object. A new format character
- 'u' indicates Py_UNICODE arrays. For those, .tounicode and
- .fromunicode methods are available. Arrays now support __iadd__
- and __imul__.
-
-- dl now builds on every system that has dlfcn.h. Failure in case
- of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
- is called.
-
-- The sys module acquired a new attribute, api_version, which evaluates
- to the value of the PYTHON_API_VERSION macro with which the
- interpreter was compiled.
-
-- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
- when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
- returns (None, None, 'ab'), as expected. Also fixed handling of
- lastindex/lastgroup match attributes in similar cases. For example,
- when running the expression r'(a)(b)?b' over 'ab', lastindex must be
- 1, not 2.
-
-- Fixed bug #581080: sre scanner was not checking the buffer limit
- before increasing the current pointer. This was creating an infinite
- loop in the search function, once the pointer exceeded the buffer
- limit.
-
-- The os.fdopen function now enforces a file mode starting with the
- letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
- bug #623464.
-
-- The linuxaudiodev module is now deprecated; it is being replaced by
- ossaudiodev. The interface has been extended to cover a lot more of
- OSS (see www.opensound.com), including most DSP ioctls and the
- OSS mixer API. Documentation forthcoming in 2.3a2.
-
-Library
--------
-
-- imaplib.py now supports SSL (Tino Lange and Piers Lauder).
-
-- Freeze's modulefinder.py has been moved to the standard library;
- slightly improved so it will issue less false missing submodule
- reports (see sf path #643711 for details). Documentation will follow
- with Python 2.3a2.
-
-- os.path exposes getctime.
-
-- unittest.py now has two additional methods called assertAlmostEqual()
- and failIfAlmostEqual(). They implement an approximate comparison
- by rounding the difference between the two arguments and comparing
- the result to zero. Approximate comparison is essential for
- unit tests of floating point results.
-
-- calendar.py now depends on the new datetime module rather than
- the time module. As a result, the range of allowable dates
- has been increased.
-
-- pdb has a new 'j(ump)' command to select the next line to be
- executed.
-
-- The distutils created windows installers now can run a
- postinstallation script.
-
-- doctest.testmod can now be called without argument, which means to
- test the current module.
-
-- When canceling a server that implemented threading with a keyboard
- interrupt, the server would shut down but not terminate (waiting on
- client threads). A new member variable, daemon_threads, was added to
- the ThreadingMixIn class in SocketServer.py to make it explicit that
- this behavior needs to be controlled.
-
-- A new module, optparse, provides a fancy alternative to getopt for
- command line parsing. It is a slightly modified version of Greg
- Ward's Optik package.
-
-- UserDict.py now defines a DictMixin class which defines all dictionary
- methods for classes that already have a minimum mapping interface.
- This greatly simplifies writing classes that need to be substitutable
- for dictionaries (such as the shelve module).
-
-- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
- all dictionary methods. This eases the transition to persistent
- storage for scripts originally written with dictionaries in mind.
-
-- shelve.open and the various classes in shelve.py now accept an optional
- binary flag, which defaults to False. If True, the values stored in the
- shelf are binary pickles.
-
-- A new package, logging, implements the logging API defined by PEP
- 282. The code is written by Vinay Sajip.
-
-- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
- modules are iterators now.
-
-- gzip.py now handles files exceeding 2GB. Files over 4GB also work
- now (provided the OS supports it, and Python is configured with large
- file support), but in that case the underlying gzip file format can
- record only the least-significant 32 bits of the file size, so that
- some tools working with gzipped files may report an incorrect file
- size.
-
-- xml.sax.saxutils.unescape has been added, to replace entity references
- with their entity value.
-
-- Queue.Queue.{put,get} now support an optional timeout argument.
-
-- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
- option of tkFileDialog is exposed as function askopenfile{,name}s.
-
-- Various configure methods of Tkinter have been stream-lined, so that
- tag_configure, image_configure, window_configure now return a
- dictionary when invoked with no argument.
-
-- Importing the readline module now no longer has the side effect of
- calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
- whatever locale is explicitly set by the user, is preserved. If you
- want repr() of 8-bit strings in your preferred encoding to preserve
- all printable characters of that encoding, you have to add the
- following code to your $PYTHONSTARTUP file or to your application's
- main():
-
- import locale
- locale.setlocale(locale.LC_CTYPE, "")
-
-- shutil.move was added. shutil.copytree now reports errors as an
- exception at the end, instead of printing error messages.
-
-- Encoding name normalization was generalized to not only
- replace hyphens with underscores, but also all other non-alphanumeric
- characters (with the exception of the dot which is used for Python
- package names during lookup). The aliases.py mapping was updated
- to the new standard.
-
-- mimetypes has two new functions: guess_all_extensions() which
- returns a list of all known extensions for a mime type, and
- add_type() which adds one mapping between a mime type and
- an extension to the database.
-
-- New module: sets, defines the class Set that implements a mutable
- set type using the keys of a dict to represent the set. There's
- also a class ImmutableSet which is useful when you need sets of sets
- or when you need to use sets as dict keys, and a class BaseSet which
- is the base class of the two.
-
-- Added random.sample(population,k) for random sampling without replacement.
- Returns a k length list of unique elements chosen from the population.
-
-- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
- OverflowError. That is, it now accepts any combination of 'start'
- and 'stop' arguments so long as each is in the range of Python's
- bounded integers.
-
-- Thanks to Raymond Hettinger, random.random() now uses a new core
- generator. The Mersenne Twister algorithm is implemented in C,
- threadsafe, faster than the previous generator, has an astronomically
- large period (2**19937-1), creates random floats to full 53-bit
- precision, and may be the most widely tested random number generator
- in existence.
-
- The random.jumpahead(n) method has different semantics for the new
- generator. Instead of jumping n steps ahead, it uses n and the
- existing state to create a new state. This means that jumpahead()
- continues to support multi-threaded code needing generators of
- non-overlapping sequences. However, it will break code which relies
- on jumpahead moving a specific number of steps forward.
-
- The attributes random.whseed and random.__whseed have no meaning for
- the new generator. Code using these attributes should switch to a
- new class, random.WichmannHill which is provided for backward
- compatibility and to make an alternate generator available.
-
-- New "algorithms" module: heapq, implements a heap queue. Thanks to
- Kevin O'Connor for the code and François Pinard for an entertaining
- write-up explaining the theory and practical uses of heaps.
-
-- New encoding for the Palm OS character set: palmos.
-
-- binascii.crc32() and the zipfile module had problems on some 64-bit
- platforms. These have been fixed. On a platform with 8-byte C longs,
- crc32() now returns a signed-extended 4-byte result, so that its value
- as a Python int is equal to the value computed a 32-bit platform.
-
-- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
- argument.
-
-- Some fixes in the copy module: when an object is copied through its
- __reduce__ method, there was no check for a __setstate__ method on
- the result [SF patch 565085]; deepcopy should treat instances of
- custom metaclasses the same way it treats instances of type 'type'
- [SF patch 560794].
-
-- Sockets now support timeout mode. After s.settimeout(T), where T is
- a float expressing seconds, subsequent operations raise an exception
- if they cannot be completed within T seconds. To disable timeout
- mode, use s.settimeout(None). There's also a module function,
- socket.setdefaulttimeout(T), which sets the default for all sockets
- created henceforth.
-
-- getopt.gnu_getopt was added. This supports GNU-style option
- processing, where options can be mixed with non-option arguments.
-
-- Stop using strings for exceptions. String objects used for
- exceptions are now classes deriving from Exception. The objects
- changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
- tabnanny.NannyNag, and xdrlib.Error.
-
-- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
- BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
- Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
- big endian systems were added to the codecs module. The old names
- BOM32_* and BOM64_* were off by a factor of 2.
-
-- Added conversion functions math.degrees() and math.radians().
-
-- math.log() now takes an optional argument: math.log(x[, base]).
-
-- ftplib.retrlines() now tests for callback is None rather than testing
- for False. Was causing an error when given a callback object which
- was callable but also returned len() as zero. The change may
- create new breakage if the caller relied on the undocumented behavior
- and called with callback set to [] or some other False value not
- identical to None.
-
-- random.gauss() uses a piece of hidden state used by nothing else,
- and the .seed() and .whseed() methods failed to reset it. In other
- words, setting the seed didn't completely determine the sequence of
- results produced by random.gauss(). It does now. Programs repeatedly
- mixing calls to a seed method with calls to gauss() may see different
- results now.
-
-- The pickle.Pickler class grew a clear_memo() method to mimic that
- provided by cPickle.Pickler.
-
-- difflib's SequenceMatcher class now does a dynamic analysis of
- which elements are so frequent as to constitute noise. For
- comparing files as sequences of lines, this generally works better
- than the IS_LINE_JUNK function, and function ndiff's linejunk
- argument defaults to None now as a result. A happy benefit is
- that SequenceMatcher may run much faster now when applied
- to large files with many duplicate lines (for example, C program
- text with lots of repeated "}" and "return NULL;" lines).
-
-- New Text.dump() method in Tkinter module.
-
-- New distutils commands for building packagers were added to
- support pkgtool on Solaris and swinstall on HP-UX.
-
-- distutils now has a new abstract binary packager base class
- command/bdist_packager, which simplifies writing packagers.
- This will hopefully provide the missing bits to encourage
- people to submit more packagers, e.g. for Debian, FreeBSD
- and other systems.
-
-- The UTF-16, -LE and -BE stream readers now raise a
- NotImplementedError for all calls to .readline(). Previously, they
- used to just produce garbage or fail with an encoding error --
- UTF-16 is a 2-byte encoding and the C lib's line reading APIs don't
- work well with these.
-
-- compileall now supports quiet operation.
-
-- The BaseHTTPServer now implements optional HTTP/1.1 persistent
- connections.
-
-- socket module: the SSL support was broken out of the main
- _socket module C helper and placed into a new _ssl helper
- which now gets imported by socket.py if available and working.
-
-- encodings package: added aliases for all supported IANA character
- sets
-
-- ftplib: to safeguard the user's privacy, anonymous login will use
- "anonymous@" as default password, rather than the real user and host
- name.
-
-- webbrowser: tightened up the command passed to os.system() so that
- arbitrary shell code can't be executed because a bogus URL was
- passed in.
-
-- gettext.translation has an optional fallback argument, and
- gettext.find an optional all argument. Translations will now fallback
- on a per-message basis. The module supports plural forms, by means
- of gettext.[d]ngettext and Translation.[u]ngettext.
-
-- distutils bdist commands now offer a --skip-build option.
-
-- warnings.warn now accepts a Warning instance as first argument.
-
-- The xml.sax.expatreader.ExpatParser class will no longer create
- circular references by using itself as the locator that gets passed
- to the content handler implementation. [SF bug #535474]
-
-- The email.Parser.Parser class now properly parses strings regardless
- of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
- or CRLF). Also, the Header class's constructor default arguments
- has changed slightly so that an explicit maxlinelen value is always
- honored, and so unicode conversion error handling can be specified.
-
-- distutils' build_ext command now links C++ extensions with the C++
- compiler available in the Makefile or CXX environment variable, if
- running under \*nix.
-
-- New module bz2: provides a comprehensive interface for the bz2 compression
- library. It implements a complete file interface, one-shot (de)compression
- functions, and types for sequential (de)compression.
-
-- New pdb command 'pp' which is like 'p' except that it pretty-prints
- the value of its expression argument.
-
-- Now bdist_rpm distutils command understands a verify_script option in
- the config file, including the contents of the referred filename in
- the "%verifyscript" section of the rpm spec file.
-
-- Fixed bug #495695: webbrowser module would run graphic browsers in a
- unix environment even if DISPLAY was not set. Also, support for
- skipstone browser was included.
-
-- Fixed bug #636769: rexec would run unallowed code if subclasses of
- strings were used as parameters for certain functions.
-
-Tools/Demos
------------
-
-- pygettext.py now supports globbing on Windows, and accepts module
- names in addition to accepting file names.
-
-- The SGI demos (Demo/sgi) have been removed. Nobody thought they
- were interesting any more. (The SGI library modules and extensions
- are still there; it is believed that at least some of these are
- still used and useful.)
-
-- IDLE supports the new encoding declarations (PEP 263); it can also
- deal with legacy 8-bit files if they use the locale's encoding. It
- allows non-ASCII strings in the interactive shell and executes them
- in the locale's encoding.
-
-- freeze.py now produces binaries which can import shared modules,
- unlike before when this failed due to missing symbol exports in
- the generated binary.
-
-Build
------
-
-- On Unix, IDLE is now installed automatically.
-
-- The fpectl module is not built by default; it's dangerous or useless
- except in the hands of experts.
-
-- The public Python C API will generally be declared using PyAPI_FUNC
- and PyAPI_DATA macros, while Python extension module init functions
- will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
- are deprecated.
-
-- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
- get into infinite loops, when a new-style class got garbage-collected.
- Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
- that new-style classes be immortal in COUNT_ALLOCS builds. Note that
- COUNT_ALLOCS is not enabled by default, in either release or debug
- builds, and that new-style classes are immortal only in COUNT_ALLOCS
- builds.
-
-- Compiling out the cyclic garbage collector is no longer an option.
- The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
- that it's always defined (for the benefit of any extension modules
- that may be conditionalizing on it). A bonus is that any extension
- type participating in cyclic gc can choose to participate in the
- Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
- to require editing the core to teach the trashcan mechanism about the
- new type.
-
-- According to Annex F of the current C standard,
-
- The Standard C macro HUGE_VAL and its float and long double analogs,
- HUGE_VALF and HUGE_VALL, expand to expressions whose values are
- positive infinities.
-
- Python only uses the double HUGE_VAL, and only to #define its own symbol
- Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
- pyport.h used to try to worm around that, but the workarounds triggered
- other bugs on other platforms, so we gave up. If your platform defines
- HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
- that works on your platform. The only instance of this I'm sure about
- is on an unknown subset of Cray systems, described here:
-
- http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
-
- Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
-
-- The configure option --without-doc-strings can be used to remove the
- doc strings from the builtin functions and modules; this reduces the
- size of the executable.
-
-- The universal newlines option (PEP 278) is on by default. On Unix
- it can be disabled by passing --without-universal-newlines to the
- configure script. On other platforms, remove
- WITH_UNIVERSAL_NEWLINES from pyconfig.h.
-
-- On Unix, a shared libpython2.3.so can be created with --enable-shared.
-
-- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
- preprocessor symbols were eliminated. The internal decisions they
- controlled stopped being experimental long ago.
-
-- The tools used to build the documentation now work under Cygwin as
- well as Unix.
-
-- The bsddb and dbm module builds have been changed to try and avoid version
- skew problems and disable linkage with Berkeley DB 1.85 unless the
- installer knows what s/he's doing. See the section on building these
- modules in the README file for details.
-
-C API
------
-
-- PyNumber_Check() now returns true for string and unicode objects.
- This is a result of these types having a partially defined
- tp_as_number slot. (This is not a feature, but an indication that
- PyNumber_Check() is not very useful to determine numeric behavior.
- It may be deprecated.)
-
-- The string object's layout has changed: the pointer member
- ob_sinterned has been replaced by an int member ob_sstate. On some
- platforms (e.g. most 64-bit systems) this may change the offset of
- the ob_sval member, so as a precaution the API_VERSION has been
- incremented. The apparently unused feature of "indirect interned
- strings", supported by the ob_sinterned member, is gone. Interned
- strings are now usually mortal; there is a new API,
- PyString_InternImmortal() that creates immortal interned strings.
- (The ob_sstate member can only take three values; however, while
- making it a char saves a few bytes per string object on average, in
- it also slowed things down a bit because ob_sval was no longer
- aligned.)
-
-- The Py_InitModule*() functions now accept NULL for the 'methods'
- argument. Modules without global functions are becoming more common
- now that factories can be types rather than functions.
-
-- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
- level.
-
-- New functions PyErr_SetExcFromWindowsErr() and
- PyErr_SetExcFromWindowsErrWithFilename(). Similar to
- PyErr_SetFromWindowsErrWithFilename() and
- PyErr_SetFromWindowsErr(), but they allow to specify
- the exception type to raise. Available on Windows.
-
-- Py_FatalError() is now declared as taking a const char* argument. It
- was previously declared without const. This should not affect working
- code.
-
-- Added new macro PySequence_ITEM(o, i) that directly calls
- sq_item without rechecking that o is a sequence and without
- adjusting for negative indices.
-
-- PyRange_New() now raises ValueError if the fourth argument is not 1.
- This is part of the removal of deprecated features of the xrange
- object.
-
-- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
- coercion if both arguments have the same type but this type has the
- CHECKTYPES flag set. This is to better support proxies.
-
-- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
- "``void (*)(void *)``".
-
-- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
-
-- A type can now inherit its metatype from its base type. Previously,
- when PyType_Ready() was called, if ob_type was found to be NULL, it
- was always set to &PyType_Type; now it is set to base->ob_type,
- where base is tp_base, defaulting to &PyObject_Type.
-
-- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
-
-- The PyCore_* family of APIs have been removed.
-
-- The "u#" parser marker will now pass through Unicode objects as-is
- without going through the buffer API.
-
-- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
-
-- An old #define of ANY as void has been removed from pyport.h. This
- hasn't been used since Python's pre-ANSI days, and the #define has
- been marked as obsolete since then. SF bug 495548 says it created
- conflicts with other packages, so keeping it around wasn't harmless.
-
-- Because Python's magic number scheme broke on January 1st, we decided
- to stop Python development. Thanks for all the fish!
-
-- Some of us don't like fish, so we changed Python's magic number
- scheme to a new one. See Python/import.c for details.
-
-New platforms
--------------
-
-- OpenVMS is now supported.
-
-- AtheOS is now supported.
-
-- the EMX runtime environment on OS/2 is now supported.
-
-- GNU/Hurd is now supported.
-
-Tests
------
-
-- The regrtest.py script's -u option now provides a way to say "allow
- all resources except this one." For example, to allow everything
- except bsddb, give the option '-uall,-bsddb'.
-
-Windows
--------
-
-- The Windows distribution now ships with version 4.0.14 of the
- Sleepycat Berkeley database library. This should be a huge
- improvement over the previous Berkeley DB 1.85, which had many
- bugs.
- XXX What are the licensing issues here?
- XXX If a user has a database created with a previous version of
- XXX Python, what must they do to convert it?
- XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
- XXX The version # is likely to change before 2.3a1.
-
-- The Windows distribution now ships with a Secure Sockets Library (SLL)
- module (_ssl.pyd)
-
-- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
- previously shipped with Tcl/Tk 8.3.2).
-
-- When Python is built under a Microsoft compiler, sys.version now
- includes the compiler version number (_MSC_VER). For example, under
- MSVC 6, sys.version contains the substring "MSC v.1200 ". 1200 is
- the value of _MSC_VER under MSVC 6.
-
-- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
- of that has been fixed in the installer (disabled Wise's "delete in-
- use files" uninstall option).
-
-- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
-
-- The installer now installs Start menu shortcuts under (the local
- equivalent of) "All Users" when doing an Admin install.
-
-- file.truncate([newsize]) now works on Windows for all newsize values.
- It used to fail if newsize didn't fit in 32 bits, reflecting a
- limitation of MS _chsize (which is no longer used).
-
-- os.waitpid() is now implemented for Windows, and can be used to block
- until a specified process exits. This is similar to, but not exactly
- the same as, os.waitpid() on POSIX systems. If you're waiting for
- a specific process whose pid was obtained from one of the spawn()
- functions, the same Python os.waitpid() code works across platforms.
- See the docs for details. The docs were changed to clarify that
- spawn functions return, and waitpid requires, a process handle on
- Windows (not the same thing as a Windows process id).
-
-- New tempfile.TemporaryFile implementation for Windows: this doesn't
- need a TemporaryFileWrapper wrapper anymore, and should be immune
- to a nasty problem: before 2.3, if you got a temp file on Windows, it
- got wrapped in an object whose close() method first closed the
- underlying file, then deleted the file. This usually worked fine.
- However, the spawn family of functions on Windows create (at a low C
- level) the same set of open files in the spawned process Q as were
- open in the spawning process P. If a temp file f was among them, then
- doing f.close() in P first closed P's C-level file handle on f, but Q's
- C-level file handle on f remained open, so the attempt in P to delete f
- blew up with a "Permission denied" error (Windows doesn't allow
- deleting open files). This was surprising, subtle, and difficult to
- work around.
-
-- The os module now exports all the symbolic constants usable with the
- low-level os.open() on Windows: the new constants in 2.3 are
- O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
- The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
- O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
- to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
- (so specify both if you want both; note that neither is useful unless
- specified with O_CREAT too).
-
-Mac
-----
-
-- Mac/Relnotes is gone, the release notes are now here.
-
-- Python (the OSX-only, unix-based version, not the OS9-compatible CFM
- version) now fully supports unicode strings as arguments to various file
- system calls, eg. open(), file(), os.stat() and os.listdir().
-
-- The current naming convention for Python on the Macintosh is that MacPython
- refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
- CFM-based version that runs on both OS9 and OSX.
-
-- All MacPython-OS9 functionality is now available in an OSX unix build,
- including the Carbon modules, the IDE, OSA support, etc. A lot of this
- will only work correctly in a framework build, though, because you cannot
- talk to the window manager unless your application is run from a .app
- bundle. There is a command line tool "pythonw" that runs your script
- with an interpreter living in such a .app bundle, this interpreter should
- be used to run any Python script using the window manager (including
- Tkinter or wxPython scripts).
-
-- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
- MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
- are specifically for MacPython-OS9 (CFM support, preference resources, etc).
-
-- A new utility PythonLauncher will start a Python interpreter when a .py or
- .pyw script is double-clicked in the Finder. By default .py scripts are
- run with a normal Python interpreter in a Terminal window and .pyw
- files are run with a window-aware pythonw interpreter without a Terminal
- window, but all this can be customized.
-
-- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
- possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
- releases.
-
-- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
- line interface too.
-
-- All the Carbon classes are now PEP253 compliant, meaning that you can
- subclass them from Python. Most of the attributes have gone, you should
- now use the accessor function call API, which is also what Apple's
- documentation uses. Some attributes such as grafport.visRgn are still
- available for convenience.
-
-- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
- and Folder (APIs from Folders.h). The old macfs builtin module is
- gone, and replaced by a Python wrapper around the new modules.
-
-- Pathname handling should now be fully consistent: MacPython-OSX always uses
- unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
- (also when running on Mac OS X).
-
-- New Carbon modules Help and AH give access to the Carbon Help Manager.
- There are hooks in the IDE to allow accessing the Python documentation
- (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
- See Mac/OSX/README for converting the Python documentation to a
- Help Viewer compatible form and installing it.
-
-- OSA support has been redesigned and the generated Python classes now
- mirror the inheritance defined by the underlying OSA classes.
-
-- MacPython no longer maps both \r and \n to \n on input for any text file.
- This feature has been replaced by universal newline support (PEP278).
-
-- The default encoding for Python sourcefiles in MacPython-OS9 is no longer
- mac-roman (or whatever your local Mac encoding was) but "ascii", like on
- other platforms. If you really need sourcefiles with Mac characters in them
- you can change this in site.py.
-
-
-What's New in Python 2.2 final?
-===============================
-
-*Release date: 21-Dec-2001*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- pickle.py, cPickle: allow pickling instances of new-style classes
- with a custom metaclass.
-
-Core and builtins
------------------
-
-- weakref proxy object: when comparing, unwrap both arguments if both
- are proxies.
-
-Extension modules
------------------
-
-- binascii.b2a_base64(): fix a potential buffer overrun when encoding
- very short strings.
-
-- cPickle: the obscure "fast" mode was suspected of causing stack
- overflows on the Mac. Hopefully fixed this by setting the recursion
- limit much smaller. If the limit is too low (it only affects
- performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
- when compiling cPickle.c (or in pyconfig.h).
-
-Library
--------
-
-- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
- close or delete time).
-
-- rfc822.py: fixed a bug where the address '<>' was converted to None
- instead of an empty string (also fixes the email.Utils module).
-
-- xmlrpclib.py: version 1.0.0; uses precision for doubles.
-
-- test suite: the pickle and cPickle tests were not executing any code
- when run from the standard regression test.
-
-Tools/Demos
------------
-
-Build
------
-
-C API
------
-
-New platforms
--------------
-
-Tests
------
-
-Windows
--------
-
-- distutils package: fixed broken Windows installers (bdist_wininst).
-
-- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
- instances are deleted at process exit time.
-
-- socket.py: prevent mysterious warnings when socket instances are
- deleted at process exit time.
-
-- posixmodule.c: fix a Windows crash with stat() of a filename ending
- in backslash.
-
-Mac
-----
-
-- The Carbon toolbox modules have been upgraded to Universal Headers
- 3.4, and experimental CoreGraphics and CarbonEvents modules have
- been added. All only for framework-enabled MacOSX.
-
-
-What's New in Python 2.2c1?
-===========================
-
-*Release date: 14-Dec-2001*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- Guido's tutorial introduction to the new type/class features has
- been extensively updated. See
-
- http://www.python.org/2.2/descrintro.html
-
- That remains the primary documentation in this area.
-
-- Fixed a leak: instance variables declared with __slots__ were never
- deleted!
-
-- The "delete attribute" method of descriptor objects is called
- __delete__, not __del__. In previous releases, it was mistakenly
- called __del__, which created an unfortunate overloading condition
- with finalizers. (The "get attribute" and "set attribute" methods
- are still called __get__ and __set__, respectively.)
-
-- Some subtle issues with the super built-in were fixed:
-
- (a) When super itself is subclassed, its __get__ method would still
- return an instance of the base class (i.e., of super).
-
- (b) super(C, C()).__class__ would return C rather than super. This
- is confusing. To fix this, I decided to change the semantics of
- super so that it only applies to code attributes, not to data
- attributes. After all, overriding data attributes is not
- supported anyway.
-
- (c) The __get__ method didn't check whether the argument was an
- instance of the type used in creation of the super instance.
-
-- Previously, hash() of an instance of a subclass of a mutable type
- (list or dictionary) would return some value, rather than raising
- TypeError. This has been fixed. Also, directly calling
- dict.__hash__ and list.__hash__ now raises the same TypeError
- (previously, these were the same as object.__hash__).
-
-- New-style objects now support deleting their __dict__. This is for
- all intents and purposes equivalent to assigning a brand new empty
- dictionary, but saves space if the object is not used further.
-
-Core and builtins
------------------
-
-- -Qnew now works as documented in PEP 238: when -Qnew is passed on
- the command line, all occurrences of "/" use true division instead
- of classic division. See the PEP for details. Note that "all"
- means all instances in library and 3rd-party modules, as well as in
- your own code. As the PEP says, -Qnew is intended for use only in
- educational environments with control over the libraries in use.
- Note that test_coercion.py in the standard Python test suite fails
- under -Qnew; this is expected, and won't be repaired until true
- division becomes the default (in the meantime, test_coercion is
- testing the current rules).
-
-- complex() now only allows the first argument to be a string
- argument, and raises TypeError if either the second arg is a string
- or if the second arg is specified when the first is a string.
-
-Extension modules
------------------
-
-- gc.get_referents was renamed to gc.get_referrers.
-
-Library
--------
-
-- Functions in the os.spawn() family now release the global interpreter
- lock around calling the platform spawn. They should always have done
- this, but did not before 2.2c1. Multithreaded programs calling
- an os.spawn function with P_WAIT will no longer block all Python threads
- until the spawned program completes. It's possible that some programs
- relies on blocking, although more likely by accident than by design.
-
-- webbrowser defaults to netscape.exe on OS/2 now.
-
-- Tix.ResizeHandle exposes detach_widget, hide, and show.
-
-- The charset alias windows_1252 has been added.
-
-- types.StringTypes is a tuple containing the defined string types;
- usually this will be (str, unicode), but if Python was compiled
- without Unicode support it will be just (str,).
-
-- The pulldom and minidom modules were synchronized to PyXML.
-
-Tools/Demos
------------
-
-- A new script called Tools/scripts/google.py was added, which fires
- off a search on Google.
-
-Build
------
-
-- Note that release builds of Python should arrange to define the
- preprocessor symbol NDEBUG on the command line (or equivalent).
- In the 2.2 pre-release series we tried to define this by magic in
- Python.h instead, but it proved to cause problems for extension
- authors. The Unix, Windows and Mac builds now all define NDEBUG in
- release builds via cmdline (or equivalent) instead. Ports to
- other platforms should do likewise.
-
-- It is no longer necessary to use --with-suffix when building on a
- case-insensitive file system (such as Mac OS X HFS+). In the build
- directory an extension is used, but not in the installed python.
-
-C API
------
-
-- New function PyDict_MergeFromSeq2() exposes the builtin dict
- constructor's logic for updating a dictionary from an iterable object
- producing key-value pairs.
-
-- PyArg_ParseTupleAndKeywords() requires that the number of entries in
- the keyword list equal the number of argument specifiers. This
- wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
- dump core in some bad cases. This has been repaired. As a result,
- PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
- previously went unchallenged.
-
-New platforms
--------------
-
-Tests
------
-
-Windows
--------
-
-Mac
-----
-
-- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
- without any trailing digits.
-
-- Changed logic for finding python home in Mac OS X framework Pythons.
- Now sys.executable points to the executable again, in stead of to
- the shared library. The latter is used only for locating the python
- home.
-
-
-What's New in Python 2.2b2?
-===========================
-
-*Release date: 16-Nov-2001*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- Multiple inheritance mixing new-style and classic classes in the
- list of base classes is now allowed, so this works now:
-
- class Classic: pass
- class Mixed(Classic, object): pass
-
- The MRO (method resolution order) for each base class is respected
- according to its kind, but the MRO for the derived class is computed
- using new-style MRO rules if any base class is a new-style class.
- This needs to be documented.
-
-- The new builtin dictionary() constructor, and dictionary type, have
- been renamed to dict. This reflects a decade of common usage.
-
-- dict() now accepts an iterable object producing 2-sequences. For
- example, dict(d.items()) == d for any dictionary d. The argument,
- and the elements of the argument, can be any iterable objects.
-
-- New-style classes can now have a __del__ method, which is called
- when the instance is deleted (just like for classic classes).
-
-- Assignment to object.__dict__ is now possible, for objects that are
- instances of new-style classes that have a __dict__ (unless the base
- class forbids it).
-
-- Methods of built-in types now properly check for keyword arguments
- (formerly these were silently ignored). The only built-in methods
- that take keyword arguments are __call__, __init__ and __new__.
-
-- The socket function has been converted to a type; see below.
-
-Core and builtins
------------------
-
-- Assignment to __debug__ raises SyntaxError at compile-time. This
- was promised when 2.1c1 was released as "What's New in Python 2.1c1"
- (see below) says.
-
-- Clarified the error messages for unsupported operands to an operator
- (like 1 + '').
-
-Extension modules
------------------
-
-- mmap has a new keyword argument, "access", allowing a uniform way for
- both Windows and Unix users to create read-only, write-through and
- copy-on-write memory mappings. This was previously possible only on
- Unix. A new keyword argument was required to support this in a
- uniform way because the mmap() signatures had diverged across
- platforms. Thanks to Jay T Miller for repairing this!
-
-- By default, the gc.garbage list now contains only those instances in
- unreachable cycles that have __del__ methods; in 2.1 it contained all
- instances in unreachable cycles. "Instances" here has been generalized
- to include instances of both new-style and old-style classes.
-
-- The socket module defines a new method for socket objects,
- sendall(). This is like send() but may make multiple calls to
- send() until all data has been sent. Also, the socket function has
- been converted to a subclassable type, like list and tuple (etc.)
- before it; socket and SocketType are now the same thing.
-
-- Various bugfixes to the curses module. There is now a test suite
- for the curses module (you have to run it manually).
-
-- binascii.b2a_base64 no longer places an arbitrary restriction of 57
- bytes on its input.
-
-Library
--------
-
-- tkFileDialog exposes a Directory class and askdirectory
- convenience function.
-
-- Symbolic group names in regular expressions must be unique. For
- example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
- single name can't mean both "group 1" and "group 2" simultaneously.
- Python 2.2 detects this error at regexp compilation time;
- previously, the error went undetected, and results were
- unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
- pattern.subn() methods have been rewritten in C. Also, an
- experimental function/method finditer() has been added, which works
- like findall() but returns an iterator.
-
-- Tix exposes more commands through the classes DirSelectBox,
- DirSelectDialog, ListNoteBook, Meter, CheckList, and the
- methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
- tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
-
-- Traceback objects are now scanned by cyclic garbage collection, so
- cycles created by casual use of sys.exc_info() no longer cause
- permanent memory leaks (provided garbage collection is enabled).
-
-- os.extsep -- a new variable needed by the RISCOS support. It is the
- separator used by extensions, and is '.' on all platforms except
- RISCOS, where it is '/'. There is no need to use this variable
- unless you have a masochistic desire to port your code to RISCOS.
-
-- mimetypes.py has optional support for non-standard, but commonly
- found types. guess_type() and guess_extension() now accept an
- optional 'strict' flag, defaulting to true, which controls whether
- recognize non-standard types or not. A few non-standard types we
- know about have been added. Also, when run as a script, there are
- new -l and -e options.
-
-- statcache is now deprecated.
-
-- email.Utils.formatdate() now produces the preferred RFC 2822 style
- dates with numeric timezones (it used to produce obsolete dates
- hard coded to "GMT" timezone). An optional 'localtime' flag is
- added to produce dates in the local timezone, with daylight savings
- time properly taken into account.
-
-- In pickle and cPickle, instead of masking errors in load() by
- transforming them into SystemError, we let the original exception
- propagate out. Also, implement support for __safe_for_unpickling__
- in pickle, as it already was supported in cPickle.
-
-Tools/Demos
------------
-
-Build
------
-
-- The dbm module is built using libdb1 if available. The bsddb module
- is built with libdb3 if available.
-
-- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
-
-C API
------
-
-- New function PySequence_Fast_GET_SIZE() returns the size of a non-
- NULL result from PySequence_Fast(), more quickly than calling
- PySequence_Size().
-
-- New argument unpacking function PyArg_UnpackTuple() added.
-
-- New functions PyObject_CallFunctionObjArgs() and
- PyObject_CallMethodObjArgs() have been added to make it more
- convenient and efficient to call functions and methods from C.
-
-- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
- possible that this will propagate errors it didn't before.
-
-- New function PyObject_CheckReadBuffer(), which returns true if its
- argument supports the single-segment readable buffer interface.
-
-New platforms
--------------
-
-- We've finally confirmed that this release builds on HP-UX 11.00,
- *with* threads, and passes the test suite.
-
-- Thanks to a series of patches from Michael Muller, Python may build
- again under OS/2 Visual Age C++.
-
-- Updated RISCOS port by Dietmar Schwertberger.
-
-Tests
------
-
-- Added a test script for the curses module. It isn't run automatically;
- regrtest.py must be run with '-u curses' to enable it.
-
-Windows
--------
-
-Mac
-----
-
-- PythonScript has been moved to unsupported and is slated to be
- removed completely in the next release.
-
-- It should now be possible to build applets that work on both OS9 and
- OSX.
-
-- The core is now linked with CoreServices not Carbon; as a side
- result, default 8bit encoding on OSX is now ASCII.
-
-- Python should now build on OSX 10.1.1
-
-
-What's New in Python 2.2b1?
-===========================
-
-*Release date: 19-Oct-2001*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- New-style classes are now always dynamic (except for built-in and
- extension types). There is no longer a performance penalty, and I
- no longer see another reason to keep this baggage around. One relic
- remains: the __dict__ of a new-style class is a read-only proxy; you
- must set the class's attribute to modify it. As a consequence, the
- __defined__ attribute of new-style types no longer exists, for lack
- of need: there is once again only one __dict__ (although in the
- future a __cache__ may be resurrected with a similar function, if I
- can prove that it actually speeds things up).
-
-- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
- always returned None, even when there was a class docstring).
-
-- doctest now finds and runs docstrings attached to new-style classes,
- class methods, static methods, and properties.
-
-Core and builtins
------------------
-
-- A very subtle syntactical pitfall in list comprehensions was fixed.
- For example: [a+b for a in 'abc', for b in 'def']. The comma in
- this example is a mistake. Previously, this would silently let 'a'
- iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
- 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
- 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
- Note that [a for a in <singleton>] is a convoluted way to say
- [<singleton>] anyway, so it's not like any expressiveness is lost.
-
-- getattr(obj, name, default) now only catches AttributeError, as
- documented, rather than returning the default value for all
- exceptions (which could mask bugs in a __getattr__ hook, for
- example).
-
-- Weak reference objects are now part of the core and offer a C API.
- A bug which could allow a core dump when binary operations involved
- proxy reference has been fixed. weakref.ReferenceError is now a
- built-in exception.
-
-- unicode(obj) now behaves more like str(obj), accepting arbitrary
- objects, and calling a __unicode__ method if it exists.
- unicode(obj, encoding) and unicode(obj, encoding, errors) still
- require an 8-bit string or character buffer argument.
-
-- isinstance() now allows any object as the first argument and a
- class, a type or something with a __bases__ tuple attribute for the
- second argument. The second argument may also be a tuple of a
- class, type, or something with __bases__, in which case isinstance()
- will return true if the first argument is an instance of any of the
- things contained in the second argument tuple. E.g.
-
- isinstance(x, (A, B))
-
- returns true if x is an instance of A or B.
-
-Extension modules
------------------
-
-- thread.start_new_thread() now returns the thread ID (previously None).
-
-- binascii has now two quopri support functions, a2b_qp and b2a_qp.
-
-- readline now supports setting the startup_hook and the
- pre_event_hook, and adds the add_history() function.
-
-- os and posix supports chroot(), setgroups() and unsetenv() where
- available. The stat(), fstat(), statvfs() and fstatvfs() functions
- now return "pseudo-sequences" -- the various fields can now be
- accessed as attributes (e.g. os.stat("/").st_mtime) but for
- backwards compatibility they also behave as a fixed-length sequence.
- Some platform-specific fields (e.g. st_rdev) are only accessible as
- attributes.
-
-- time: localtime(), gmtime() and strptime() now return a
- pseudo-sequence similar to the os.stat() return value, with
- attributes like tm_year etc.
-
-- Decompression objects in the zlib module now accept an optional
- second parameter to decompress() that specifies the maximum amount
- of memory to use for the uncompressed data.
-
-- optional SSL support in the socket module now exports OpenSSL
- functions RAND_add(), RAND_egd(), and RAND_status(). These calls
- are useful on platforms like Solaris where OpenSSL does not
- automatically seed its PRNG. Also, the keyfile and certfile
- arguments to socket.ssl() are now optional.
-
-- posixmodule (and by extension, the os module on POSIX platforms) now
- exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
-
-Library
--------
-
-- doctest now excludes functions and classes not defined by the module
- being tested, thanks to Tim Hochberg.
-
-- HotShot, a new profiler implemented using a C-based callback, has
- been added. This substantially reduces the overhead of profiling,
- but it is still quite preliminary. Support modules and
- documentation will be added in upcoming releases (before 2.2 final).
-
-- profile now produces correct output in situations where an exception
- raised in Python is cleared by C code (e.g. hasattr()). This used
- to cause wrong output, including spurious claims of recursive
- functions and attribution of time spent to the wrong function.
-
- The code and documentation for the derived OldProfile and HotProfile
- profiling classes was removed. The code hasn't worked for years (if
- you tried to use them, they raised exceptions). OldProfile
- intended to reproduce the behavior of the profiler Python used more
- than 7 years ago, and isn't interesting anymore. HotProfile intended
- to provide a faster profiler (but producing less information), and
- that's a worthy goal we intend to meet via a different approach (but
- without losing information).
-
-- Profile.calibrate() has a new implementation that should deliver
- a much better system-specific calibration constant. The constant can
- now be specified in an instance constructor, or as a Profile class or
- instance variable, instead of by editing profile.py's source code.
- Calibration must still be done manually (see the docs for the profile
- module).
-
- Note that Profile.calibrate() must be overridden by subclasses.
- Improving the accuracy required exploiting detailed knowledge of
- profiler internals; the earlier method abstracted away the details
- and measured a simplified model instead, but consequently computed
- a constant too small by a factor of 2 on some modern machines.
-
-- quopri's encode and decode methods take an optional header parameter,
- which indicates whether output is intended for the header 'Q'
- encoding.
-
-- The SocketServer.ThreadingMixIn class now closes the request after
- finish_request() returns. (Not when it errors out though.)
-
-- The nntplib module's NNTP.body() method has grown a 'file' argument
- to allow saving the message body to a file.
-
-- The email package has added a class email.Parser.HeaderParser which
- only parses headers and does not recurse into the message's body.
- Also, the module/class MIMEAudio has been added for representing
- audio data (contributed by Anthony Baxter).
-
-- ftplib should be able to handle files > 2GB.
-
-- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
- ON, and OFF.
-
-- xml.dom.minidom NodeList objects now support the length attribute
- and item() method as required by the DOM specifications.
-
-Tools/Demos
------------
-
-- Demo/dns was removed. It no longer serves any purpose; a package
- derived from it is now maintained by Anthony Baxter, see
- http://PyDNS.SourceForge.net.
-
-- The freeze tool has been made more robust, and two new options have
- been added: -X and -E.
-
-Build
------
-
-- configure will use CXX in LINKCC if CXX is used to build main() and
- the system requires to link a C++ main using the C++ compiler.
-
-C API
------
-
-- The documentation for the tp_compare slot is updated to require that
- the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
- not correct. This is not yet enforced but will be enforced in
- Python 2.3; even later, we may use -2 to indicate errors and +2 for
- "NotImplemented". Right now, -1 should be used for an error return.
-
-- PyLong_AsLongLong() now accepts int (as well as long) arguments.
- Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
- as long) arguments.
-
-- PyThread_start_new_thread() now returns a long int giving the thread
- ID, if one can be calculated; it returns -1 for error, 0 if no
- thread ID is calculated (this is an incompatible change, but only
- the thread module used this API). This code has only really been
- tested on Linux and Windows; other platforms please beware (and
- report any bugs or strange behavior).
-
-- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
- input.
-
-New platforms
--------------
-
-Tests
------
-
-Windows
--------
-
-- Installer: If you install IDLE, and don't disable file-extension
- registration, a new "Edit with IDLE" context (right-click) menu entry
- is created for .py and .pyw files.
-
-- The signal module now supports SIGBREAK on Windows, thanks to Steven
- Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
- action remains to call Win32 ExitProcess(). This can be changed via
- signal.signal(). For example::
-
- # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
- # (SIGINT) behavior.
- import signal
- signal.signal(signal.SIGBREAK, signal.default_int_handler)
-
- try:
- while 1:
- pass
- except KeyboardInterrupt:
- # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
- # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
- # program without the possibility for any Python-level cleanup).
- print "Clean exit"
-
-
-What's New in Python 2.2a4?
-===========================
-
-*Release date: 28-Sep-2001*
-
-Type/class unification and new-style classes
---------------------------------------------
-
-- pydoc and inspect are now aware of new-style classes;
- e.g. help(list) at the interactive prompt now shows proper
- documentation for all operations on list objects.
-
-- Applications using Jim Fulton's ExtensionClass module can now safely
- be used with Python 2.2. In particular, Zope 2.4.1 now works with
- Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
- examples also work again. It is hoped that Gtk and Boost also work
- with 2.2a4 and beyond. (If you can confirm this, please write
- webmaster at python.org; if there are still problems, please open a bug
- report on SourceForge.)
-
-- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
- These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
- in the constructed property object. fget, fset and fdel weren't
- discoverable from Python in 2.2a3. __doc__ is new, and allows to
- associate a docstring with a property.
-
-- Comparison overloading is now more completely implemented. For
- example, a str subclass instance can properly be compared to a str
- instance, and it can properly overload comparison. Ditto for most
- other built-in object types.
-
-- The repr() of new-style classes has changed; instead of <type
- 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
- *except* for built-in types, which are still rendered as <type
- 'Foo'> (to avoid upsetting existing code that might parse or
- otherwise rely on repr() of certain type objects).
-
-- The repr() of new-style objects is now always <Foo object at XXX>;
- previously, it was sometimes <Foo instance at XXX>.
-
-- For new-style classes, what was previously called __getattr__ is now
- called __getattribute__. This method, if defined, is called for
- *every* attribute access. A new __getattr__ hook more similar to the
- one in classic classes is defined which is called only if regular
- attribute access raises AttributeError; to catch *all* attribute
- access, you can use __getattribute__ (for new-style classes). If
- both are defined, __getattribute__ is called first, and if it raises
- AttributeError, __getattr__ is called.
-
-- The __class__ attribute of new-style objects can be assigned to.
- The new class must have the same C-level object layout as the old
- class.
-
-- The builtin file type can be subclassed now. In the usual pattern,
- "file" is the name of the builtin type, and file() is a new builtin
- constructor, with the same signature as the builtin open() function.
- file() is now the preferred way to open a file.
-
-- Previously, __new__ would only see sequential arguments passed to
- the type in a constructor call; __init__ would see both sequential
- and keyword arguments. This made no sense whatsoever any more, so
- now both __new__ and __init__ see all arguments.
-
-- Previously, hash() applied to an instance of a subclass of str or
- unicode always returned 0. This has been repaired.
-
-- Previously, an operation on an instance of a subclass of an
- immutable type (int, long, float, complex, tuple, str, unicode),
- where the subtype didn't override the operation (and so the
- operation was handled by the builtin type), could return that
- instance instead a value of the base type. For example, if s was of
- a str subclass type, s[:] returned s as-is. Now it returns a str
- with the same value as s.
-
-- Provisional support for pickling new-style objects has been added.
-
-Core
-----
-
-- file.writelines() now accepts any iterable object producing strings.
-
-- PyUnicode_FromEncodedObject() now works very much like
- PyObject_Str(obj) in that it tries to use __str__/tp_str
- on the object if the object is not a string or buffer. This
- makes unicode() behave like str() when applied to non-string/buffer
- objects.
-
-- PyFile_WriteObject now passes Unicode objects to the file's write
- method. As a result, all file-like objects which may be the target
- of a print statement must support Unicode objects, i.e. they must
- at least convert them into ASCII strings.
-
-- Thread scheduling on Solaris should be improved; it is no longer
- necessary to insert a small sleep at the start of a thread in order
- to let other runnable threads be scheduled.
-
-Library
--------
-
-- StringIO.StringIO instances and cStringIO.StringIO instances support
- read character buffer compatible objects for their .write() methods.
- These objects are converted to strings and then handled as such
- by the instances.
-
-- The "email" package has been added. This is basically a port of the
- mimelib package <http://sf.net/projects/mimelib> with API changes
- and some implementations updated to use iterators and generators.
-
-- difflib.ndiff() and difflib.Differ.compare() are generators now. This
- restores the ability of Tools/scripts/ndiff.py to start producing output
- before the entire comparison is complete.
-
-- StringIO.StringIO instances and cStringIO.StringIO instances support
- iteration just like file objects (i.e. their .readline() method is
- called for each iteration until it returns an empty string).
-
-- The codecs module has grown four new helper APIs to access
- builtin codecs: getencoder(), getdecoder(), getreader(),
- getwriter().
-
-- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
- simplifies writing XML RPC servers.
-
-- os.path.realpath(): a new function that returns the absolute pathname
- after interpretation of symbolic links. On non-Unix systems, this
- is an alias for os.path.abspath().
-
-- operator.indexOf() (PySequence_Index() in the C API) now works with any
- iterable object.
-
-- smtplib now supports various authentication and security features of
- the SMTP protocol through the new login() and starttls() methods.
-
-- hmac: a new module implementing keyed hashing for message
- authentication.
-
-- mimetypes now recognizes more extensions and file types. At the
- same time, some mappings not sanctioned by IANA were removed.
-
-- The "compiler" package has been brought up to date to the state of
- Python 2.2 bytecode generation. It has also been promoted from a
- Tool to a standard library package. (Tools/compiler still exists as
- a sample driver.)
-
-Build
------
-
-- Large file support (LFS) is now automatic when the platform supports
- it; no more manual configuration tweaks are needed. On Linux, at
- least, it's possible to have a system whose C library supports large
- files but whose kernel doesn't; in this case, large file support is
- still enabled but doesn't do you any good unless you upgrade your
- kernel or share your Python executable with another system whose
- kernel has large file support.
-
-- The configure script now supplies plausible defaults in a
- cross-compilation environment. This doesn't mean that the supplied
- values are always correct, or that cross-compilation now works
- flawlessly -- but it's a first step (and it shuts up most of
- autoconf's warnings about AC_TRY_RUN).
-
-- The Unix build is now a bit less chatty, courtesy of the parser
- generator. The build is completely silent (except for errors) when
- using "make -s", thanks to a -q option to setup.py.
-
-C API
------
-
-- The "structmember" API now supports some new flag bits to deny read
- and/or write access to attributes in restricted execution mode.
-
-New platforms
--------------
-
-- Compaq's iPAQ handheld, running the "familiar" Linux distribution
- (http://familiar.handhelds.org).
-
-Tests
------
-
-- The "classic" standard tests, which work by comparing stdout to
- an expected-output file under Lib/test/output/, no longer stop at
- the first mismatch. Instead the test is run to completion, and a
- variant of ndiff-style comparison is used to report all differences.
- This is much easier to understand than the previous style of reporting.
-
-- The unittest-based standard tests now use regrtest's test_main()
- convention, instead of running as a side-effect of merely being
- imported. This allows these tests to be run in more natural and
- flexible ways as unittests, outside the regrtest framework.
-
-- regrtest.py is much better integrated with unittest and doctest now,
- especially in regard to reporting errors.
-
-Windows
--------
-
-- Large file support now also works for files > 4GB, on filesystems
- that support it (NTFS under Windows 2000). See "What's New in
- Python 2.2a3" for more detail.
-
-
-What's New in Python 2.2a3?
-===========================
-
-*Release Date: 07-Sep-2001*
-
-Core
-----
-
-- Conversion of long to float now raises OverflowError if the long is too
- big to represent as a C double.
-
-- The 3-argument builtin pow() no longer allows a third non-None argument
- if either of the first two arguments is a float, or if both are of
- integer types and the second argument is negative (in which latter case
- the arguments are converted to float, so this is really the same
- restriction).
-
-- The builtin dir() now returns more information, and sometimes much
- more, generally naming all attributes of an object, and all attributes
- reachable from the object via its class, and from its class's base
- classes, and so on from them too. Example: in 2.2a2, dir([]) returned
- an empty list. In 2.2a3,
-
- >>> dir([])
- ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
- '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
- '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
- '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
- '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
- 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
- 'reverse', 'sort']
-
- dir(module) continues to return only the module's attributes, though.
-
-- Overflowing operations on plain ints now return a long int rather
- than raising OverflowError. This is a partial implementation of PEP
- 237. You can use -Wdefault::OverflowWarning to enable a warning for
- this situation, and -Werror::OverflowWarning to revert to the old
- OverflowError exception.
-
-- A new command line option, -Q<arg>, is added to control run-time
- warnings for the use of classic division. (See PEP 238.) Possible
- values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
- -Qold, meaning the / operator has its classic meaning and no
- warnings are issued. Using -Qwarn issues a run-time warning about
- all uses of classic division for int and long arguments; -Qwarnall
- also warns about classic division for float and complex arguments
- (for use with fixdiv.py).
- [Note: the remainder of this item (preserved below) became
- obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
-
- Using -Qnew is questionable; it turns on new division by default, but
- only in the __main__ module. You can usefully combine -Qwarn or
- -Qwarnall and -Qnew: this gives the __main__ module new division, and
- warns about classic division everywhere else.
-
-- Many built-in types can now be subclassed. This applies to int,
- long, float, str, unicode, and tuple. (The types complex, list and
- dictionary can also be subclassed; this was introduced earlier.)
- Note that restrictions apply when subclassing immutable built-in
- types: you can only affect the value of the instance by overloading
- __new__. You can add mutable attributes, and the subclass instances
- will have a __dict__ attribute, but you cannot change the "value"
- (as implemented by the base class) of an immutable subclass instance
- once it is created.
-
-- The dictionary constructor now takes an optional argument, a
- mapping-like object, and initializes the dictionary from its
- (key, value) pairs.
-
-- A new built-in type, super, has been added. This facilitates making
- "cooperative super calls" in a multiple inheritance setting. For an
- explanation, see http://www.python.org/2.2/descrintro.html#cooperation
-
-- A new built-in type, property, has been added. This enables the
- creation of "properties". These are attributes implemented by
- getter and setter functions (or only one of these for read-only or
- write-only attributes), without the need to override __getattr__.
- See http://www.python.org/2.2/descrintro.html#property
-
-- The syntax of floating-point and imaginary literals has been
- liberalized, to allow leading zeroes. Examples of literals now
- legal that were SyntaxErrors before:
-
- 00.0 0e3 0100j 07.5 00000000000000000008.
-
-- An old tokenizer bug allowed floating point literals with an incomplete
- exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
-
-Library
--------
-
-- telnetlib includes symbolic names for the options, and support for
- setting an option negotiation callback. It also supports processing
- of suboptions.
-
-- The new C standard no longer requires that math libraries set errno to
- ERANGE on overflow. For platform libraries that exploit this new
- freedom, Python's overflow-checking was wholly broken. A new overflow-
- checking scheme attempts to repair that, but may not be reliable on all
- platforms (C doesn't seem to provide anything both useful and portable
- in this area anymore).
-
-- Asynchronous timeout actions are available through the new class
- threading.Timer.
-
-- math.log and math.log10 now return sensible results for even huge
- long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
-
-- A new function, imp.lock_held(), returns 1 when the import lock is
- currently held. See the docs for the imp module.
-
-- pickle, cPickle and marshal on 32-bit platforms can now correctly read
- dumps containing ints written on platforms where Python ints are 8 bytes.
- When read on a box where Python ints are 4 bytes, such values are
- converted to Python longs.
-
-- In restricted execution mode (using the rexec module), unmarshalling
- code objects is no longer allowed. This plugs a security hole.
-
-- unittest.TestResult instances no longer store references to tracebacks
- generated by test failures. This prevents unexpected dangling references
- to objects that should be garbage collected between tests.
-
-Tools
------
-
-- Tools/scripts/fixdiv.py has been added which can be used to fix
- division operators as per PEP 238.
-
-Build
------
-
-- If you are an adventurous person using Mac OS X you may want to look at
- Mac/OSX. There is a Makefile there that will build Python as a real Mac
- application, which can be used for experimenting with Carbon or Cocoa.
- Discussion of this on pythonmac-sig, please.
-
-C API
------
-
-- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
-
-- Note that PyLong_AsDouble can fail! This has always been true, but no
- callers checked for it. It's more likely to fail now, because overflow
- errors are properly detected now. The proper way to check::
-
- double x = PyLong_AsDouble(some_long_object);
- if (x == -1.0 && PyErr_Occurred()) {
- /* The conversion failed. */
- }
-
-- The GC API has been changed. Extensions that use the old API will still
- compile but will not participate in GC. To upgrade an extension
- module:
-
- - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
-
- - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
- PyObject_GC_Del to deallocate them
-
- - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
- to PyObject_GC_UnTrack
-
- - remove PyGC_HEAD_SIZE from object size calculations
-
- - remove calls to PyObject_AS_GC and PyObject_FROM_GC
-
-- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
- These can be used safely to construct string objects from a
- sprintf-style format string (similar to the format string supported
- by PyErr_Format()).
-
-New platforms
--------------
-
-- Stephen Hansen contributed patches sufficient to get a clean compile
- under Borland C (Windows), but he reports problems running it and ran
- out of time to complete the port. Volunteers? Expect a MemoryError
- when importing the types module; this is probably shallow, and
- causing later failures too.
-
-Tests
------
-
-Windows
--------
-
-- Large file support is now enabled on Win32 platforms as well as on
- Win64. This means that, for example, you can use f.tell() and f.seek()
- to manipulate files larger than 2 gigabytes (provided you have enough
- disk space, and are using a Windows filesystem that supports large
- partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
- filesize limit, and large file support makes no difference there.
- FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
- NTFS has no practical limit on file size, and files of any size can be
- used from Python now.
-
-- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
- points to command.com (patch from Brian Quinlan).
-
-
-What's New in Python 2.2a2?
-===========================
-
-*Release Date: 22-Aug-2001*
-
-Build
------
-
-- Tim Peters developed a brand new Windows installer using Wise 8.1,
- generously donated to us by Wise Solutions.
-
-- configure supports a new option --enable-unicode, with the values
- ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
- type and supporting code is completely removed from the interpreter.
-
-- A new configure option --enable-framework builds a Mac OS X framework,
- which "make frameworkinstall" will install. This provides a starting
- point for more mac-like functionality, join pythonmac-sig at python.org
- if you are interested in helping.
-
-- The NeXT platform is no longer supported.
-
-- The 'new' module is now statically linked.
-
-Tools
------
-
-- The new Tools/scripts/cleanfuture.py can be used to automatically
- edit out obsolete future statements from Python source code. See
- the module docstring for details.
-
-Tests
------
-
-- regrtest.py now knows which tests are expected to be skipped on some
- platforms, allowing to give clearer test result output. regrtest
- also has optional --use/-u switch to run normally disabled tests
- which require network access or consume significant disk resources.
-
-- Several new tests in the standard test suite, with special thanks to
- Nick Mathewson.
-
-Core
-----
-
-- The floor division operator // has been added as outlined in PEP
- 238. The / operator still provides classic division (and will until
- Python 3.0) unless "from __future__ import division" is included, in
- which case the / operator will provide true division. The operator
- module provides truediv() and floordiv() functions. Augmented
- assignment variants are included, as are the equivalent overloadable
- methods and C API methods. See the PEP for a full discussion:
- <http://python.sf.net/peps/pep-0238.html>
-
-- Future statements are now effective in simulated interactive shells
- (like IDLE). This should "just work" by magic, but read Michael
- Hudson's "Future statements in simulated shells" PEP 264 for full
- details: <http://python.sf.net/peps/pep-0264.html>.
-
-- The type/class unification (PEP 252-253) was integrated into the
- trunk and is not so tentative any more (the exact specification of
- some features is still tentative). A lot of work has done on fixing
- bugs and adding robustness and features (performance still has to
- come a long way).
-
-- Warnings about a mismatch in the Python API during extension import
- now use the Python warning framework (which makes it possible to
- write filters for these warnings).
-
-- A function's __dict__ (aka func_dict) will now always be a
- dictionary. It used to be possible to delete it or set it to None,
- but now both actions raise TypeErrors. It is still legal to set it
- to a dictionary object. Getting func.__dict__ before any attributes
- have been assigned now returns an empty dictionary instead of None.
-
-- A new command line option, -E, was added which disables the use of
- all environment variables, or at least those that are specifically
- significant to Python. Usually those have a name starting with
- "PYTHON". This was used to fix a problem where the tests fail if
- the user happens to have PYTHONHOME or PYTHONPATH pointing to an
- older distribution.
-
-Library
--------
-
-- New class Differ and new functions ndiff() and restore() in difflib.py.
- These package the algorithms used by the popular Tools/scripts/ndiff.py,
- for programmatic reuse.
-
-- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
- value using the minimal quoting required for the value; more
- reliable than using xml.sax.saxutils.escape() for attribute values.
-
-- Readline completion support for cmd.Cmd was added.
-
-- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
-
-- Added function threading.BoundedSemaphore()
-
-- Added Ka-Ping Yee's cgitb.py module.
-
-- The 'new' module now exposes the CO_xxx flags.
-
-- The gc module offers the get_referents function.
-
-New platforms
--------------
-
-C API
------
-
-- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
- which provide a cross-platform implementations for the
- relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
- the standard sprintf() and vsprintf() C lib APIs, these versions
- apply bounds checking on the used buffer which enhances protection
- against buffer overruns.
-
-- Unicode APIs now use name mangling to assure that mixing interpreters
- and extensions using different Unicode widths is rendered next to
- impossible. Trying to import an incompatible Unicode-aware extension
- will result in an ImportError. Unicode extensions writers must make
- sure to check the Unicode width compatibility in their extensions by
- using at least one of the mangled Unicode APIs in the extension.
-
-- Two new flags METH_NOARGS and METH_O are available in method definition
- tables to simplify implementation of methods with no arguments and a
- single untyped argument. Calling such methods is more efficient than
- calling corresponding METH_VARARGS methods. METH_OLDARGS is now
- deprecated.
-
-Windows
--------
-
-- "import module" now compiles module.pyw if it exists and nothing else
- relevant is found.
-
-
-What's New in Python 2.2a1?
-===========================
-
-*Release date: 18-Jul-2001*
-
-Core
-----
-
-- TENTATIVELY, a large amount of code implementing much of what's
- described in PEP 252 (Making Types Look More Like Classes) and PEP
- 253 (Subtyping Built-in Types) was added. This will be released
- with Python 2.2a1. Documentation will be provided separately
- through http://www.python.org/2.2/. The purpose of releasing this
- with Python 2.2a1 is to test backwards compatibility. It is
- possible, though not likely, that a decision is made not to release
- this code as part of 2.2 final, if any serious backwards
- incompatibilities are found during alpha testing that cannot be
- repaired.
-
-- Generators were added; this is a new way to create an iterator (see
- below) using what looks like a simple function containing one or
- more 'yield' statements. See PEP 255. Since this adds a new
- keyword to the language, this feature must be enabled by including a
- future statement: "from __future__ import generators" (see PEP 236).
- Generators will become a standard feature in a future release
- (probably 2.3). Without this future statement, 'yield' remains an
- ordinary identifier, but a warning is issued each time it is used.
- (These warnings currently don't conform to the warnings framework of
- PEP 230; we intend to fix this in 2.2a2.)
-
-- The UTF-16 codec was modified to be more RFC compliant. It will now
- only remove BOM characters at the start of the string and then
- only if running in native mode (UTF-16-LE and -BE won't remove a
- leading BMO character).
-
-- Strings now have a new method .decode() to complement the already
- existing .encode() method. These two methods provide direct access
- to the corresponding decoders and encoders of the registered codecs.
-
- To enhance the usability of the .encode() method, the special
- casing of Unicode object return values was dropped (Unicode objects
- were auto-magically converted to string using the default encoding).
-
- Both methods will now return whatever the codec in charge of the
- requested encoding returns as object, e.g. Unicode codecs will
- return Unicode objects when decoding is requested ("äöü".decode("latin-1")
- will return u"äöü"). This enables codec writer to create codecs
- for various simple to use conversions.
-
- New codecs were added to demonstrate these new features (the .encode()
- and .decode() columns indicate the type of the returned objects):
-
- +---------+-----------+-----------+-----------------------------+
- |Name | .encode() | .decode() | Description |
- +=========+===========+===========+=============================+
- |uu | string | string | UU codec (e.g. for email) |
- +---------+-----------+-----------+-----------------------------+
- |base64 | string | string | base64 codec |
- +---------+-----------+-----------+-----------------------------+
- |quopri | string | string | quoted-printable codec |
- +---------+-----------+-----------+-----------------------------+
- |zlib | string | string | zlib compression |
- +---------+-----------+-----------+-----------------------------+
- |hex | string | string | 2-byte hex codec |
- +---------+-----------+-----------+-----------------------------+
- |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
- +---------+-----------+-----------+-----------------------------+
-
-- Some operating systems now support the concept of a default Unicode
- encoding for file system operations. Notably, Windows supports 'mbcs'
- as the default. The Macintosh will also adopt this concept in the medium
- term, although the default encoding for that platform will be other than
- 'mbcs'.
-
- On operating system that support non-ASCII filenames, it is common for
- functions that return filenames (such as os.listdir()) to return Python
- string objects pre-encoded using the default file system encoding for
- the platform. As this encoding is likely to be different from Python's
- default encoding, converting this name to a Unicode object before passing
- it back to the Operating System would result in a Unicode error, as Python
- would attempt to use its default encoding (generally ASCII) rather than
- the default encoding for the file system.
-
- In general, this change simply removes surprises when working with
- Unicode and the file system, making these operations work as you expect,
- increasing the transparency of Unicode objects in this context.
- See [????] for more details, including examples.
-
-- Float (and complex) literals in source code were evaluated to full
- precision only when running from a .py file; the same code loaded from a
- .pyc (or .pyo) file could suffer numeric differences starting at about the
- 12th significant decimal digit. For example, on a machine with IEEE-754
- floating arithmetic,
-
- x = 9007199254740992.0
- print long(x)
-
- printed 9007199254740992 if run directly from .py, but 9007199254740000
- if from a compiled (.pyc or .pyo) file. This was due to marshal using
- str(float) instead of repr(float) when building code objects. marshal
- now uses repr(float) instead, which should reproduce floats to full
- machine precision (assuming the platform C float<->string I/O conversion
- functions are of good quality).
-
- This may cause floating-point results to change in some cases, and
- usually for the better, but may also cause numerically unstable
- algorithms to break.
-
-- The implementation of dicts suffers fewer collisions, which has speed
- benefits. However, the order in which dict entries appear in dict.keys(),
- dict.values() and dict.items() may differ from previous releases for a
- given dict. Nothing is defined about this order, so no program should
- rely on it. Nevertheless, it's easy to write test cases that rely on the
- order by accident, typically because of printing the str() or repr() of a
- dict to an "expected results" file. See Lib/test/test_support.py's new
- sortdict(dict) function for a simple way to display a dict in sorted
- order.
-
-- Many other small changes to dicts were made, resulting in faster
- operation along the most common code paths.
-
-- Dictionary objects now support the "in" operator: "x in dict" means
- the same as dict.has_key(x).
-
-- The update() method of dictionaries now accepts generic mapping
- objects. Specifically the argument object must support the .keys()
- and __getitem__() methods. This allows you to say, for example,
- {}.update(UserDict())
-
-- Iterators were added; this is a generalized way of providing values
- to a for loop. See PEP 234. There's a new built-in function iter()
- to return an iterator. There's a new protocol to get the next value
- from an iterator using the next() method (in Python) or the
- tp_iternext slot (in C). There's a new protocol to get iterators
- using the __iter__() method (in Python) or the tp_iter slot (in C).
- Iterating (i.e. a for loop) over a dictionary generates its keys.
- Iterating over a file generates its lines.
-
-- The following functions were generalized to work nicely with iterator
- arguments::
-
- map(), filter(), reduce(), zip()
- list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
- max(), min()
- join() method of strings
- extend() method of lists
- 'x in y' and 'x not in y' (PySequence_Contains() in C API)
- operator.countOf() (PySequence_Count() in C API)
- right-hand side of assignment statements with multiple targets, such as ::
- x, y, z = some_iterable_object_returning_exactly_3_values
-
-- Accessing module attributes is significantly faster (for example,
- random.random or os.path or yourPythonModule.yourAttribute).
-
-- Comparing dictionary objects via == and != is faster, and now works even
- if the keys and values don't support comparisons other than ==.
-
-- Comparing dictionaries in ways other than == and != is slower: there were
- insecurities in the dict comparison implementation that could cause Python
- to crash if the element comparison routines for the dict keys and/or
- values mutated the dicts. Making the code bulletproof slowed it down.
-
-- Collisions in dicts are resolved via a new approach, which can help
- dramatically in bad cases. For example, looking up every key in a dict
- d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
- faster now. Thanks to Christian Tismer for pointing out the cause and
- the nature of an effective cure (last December! better late than never).
-
-- repr() is much faster for large containers (dict, list, tuple).
-
-
-Library
--------
-
-- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
- were added to the string module. These a locale-independent
- constants, unlike letters, lowercase, and uppercase. These are now
- use in appropriate locations in the standard library.
-
-- The flags used in dlopen calls can now be configured using
- sys.setdlopenflags and queried using sys.getdlopenflags.
-
-- Fredrik Lundh's xmlrpclib is now a standard library module. This
- provides full client-side XML-RPC support. In addition,
- Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
- one asyncore-based). Thanks to Eric Raymond for the documentation.
-
-- The xrange() object is simplified: it no longer supports slicing,
- repetition, comparisons, efficient 'in' checking, the tolist()
- method, or the start, stop and step attributes. See PEP 260.
-
-- A new function fnmatch.filter to filter lists of file names was added.
-
-- calendar.py uses month and day names based on the current locale.
-
-- strop is now *really* obsolete (this was announced before with 1.6),
- and issues DeprecationWarning when used (except for the four items
- that are still imported into string.py).
-
-- Cookie.py now sorts key+value pairs by key in output strings.
-
-- pprint.isrecursive(object) didn't correctly identify recursive objects.
- Now it does.
-
-- pprint functions now much faster for large containers (tuple, list, dict).
-
-- New 'q' and 'Q' format codes in the struct module, corresponding to C
- types "long long" and "unsigned long long" (on Windows, __int64). In
- native mode, these can be used only when the platform C compiler supports
- these types (when HAVE_LONG_LONG is #define'd by the Python config
- process), and then they inherit the sizes and alignments of the C types.
- In standard mode, 'q' and 'Q' are supported on all platforms, and are
- 8-byte integral types.
-
-- The site module installs a new built-in function 'help' that invokes
- pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
- it displays a message reminding the user to use 'help()' or
- 'help(object)'.
-
-Tests
------
-
-- New test_mutants.py runs dict comparisons where the key and value
- comparison operators mutate the dicts randomly during comparison. This
- rapidly causes Python to crash under earlier releases (not for the faint
- of heart: it can also cause Win9x to freeze or reboot!).
-
-- New test_pprint.py verifies that pprint.isrecursive() and
- pprint.isreadable() return sensible results. Also verifies that simple
- cases produce correct output.
-
-C API
------
-
-- Removed the unused last_is_sticky argument from the internal
- _PyTuple_Resize(). If this affects you, you were cheating.
-
----
**(For information about older versions, consult the HISTORY file.)**
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