Mailman 3 March 2001 - Python-Dev

Re: [Python-Dev] Assigning to __debug__
by Paul F. Dubois 30 Mar '01

30 Mar '01

FWIW, this change broke a lot of my code and it took an hour or two to fix it. I too was misled by the wording when __debug__ was introduced. I could swear there were even examples of assigning to it, but maybe I'm dreaming. Anyway, I thought I could. Regardless of my delusions, this is another change that breaks code in the middle of a beta cycle. I think that is not a good thing. It is one thing when one goes to get a new beta or alpha; you expect to spend some time then. It is another when one has been a good soldier and tried the beta and is now using it for routine work and updating to a new version of it breaks something because someone thought it ought to be broken. (If I don't use it for my work I certainly won't find any problems with it). I realize that this can't be a hard and fast rule but I think this one in particular deserves warning status now and change in 2.2.

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[Very Long 23kb] List of Patches to Go in 2.0.1
by Moshe Zadka 30 Mar '01

30 Mar '01

After labouring over the list of log messages for 2-3 days, I finally have a tentative list of changes. I present it as a list of checkin messages, complete with the versions. Sometimes I concatenated several consecutive checkins into one -- "I fixed the bug", "oops, typo last fix" and similar. Please go over the list and see if there's anything you feel should not go. I'll write a short script that will dump patches files later today, so I can start applying soon -- so please looking at it and see I have not made any terrible mistakes. Thanks in advance Wholesale: Lib/tempfile.py (modulu __all__) Lib/sre.py Lib/sre_compile.py Lib/sre_constants.py Lib/sre_parse.py Modules/_sre.c ---------------------------- Lib/locale.py, 1.15->1.16 setlocale(): In _locale-missing compatibility function, string comparison should be done with != instead of "is not". ---------------------------- Lib/xml/dom/pulldom.py, 1.20->1.21 When creating an attribute node using createAttribute() or createAttributeNS(), use the parallel setAttributeNode() or setAttributeNodeNS() to add the node to the document -- do not assume that setAttributeNode() will operate properly for both. ---------------------------- Python/pythonrun.c, 2.128->2.129 Fix memory leak with SyntaxError. (The DECREF was originally hidden inside a piece of code that was deemed reduntant; the DECREF was unfortunately *not* redundant!) ---------------------------- Lib/quopri.py, 1.10->1.11 Strip \r as trailing whitespace as part of soft line endings. Inspired by SF patch #408597 (Walter Dörwald): quopri, soft line breaks and CRLF. (I changed (" ", "\t", "\r") into " \t\r".) ---------------------------- Modules/bsddbmodule.c, 1.28->1.29 Don't raise MemoryError in keys() when the database is empty. This fixes SF bug #410146 (python 2.1b shelve is broken). ---------------------------- Lib/fnmatch.py, 1.10->1.11 Donovan Baarda <abo(a)users.sourceforge.net>: Patch to make "\" in a character group work properly. This closes SF bug #409651. ---------------------------- Objects/complexobject.c, 2.34->2.35 SF bug [ #409448 ] Complex division is braindead http://sourceforge.net/tracker/?func=detail&aid=409448&group_id=5470&atid=1… Now less braindead. Also added test_complex.py, which doesn't test much, but fails without this patch. ---------------------------- Modules/cPickle.c, 2.54->2.55 SF bug [ #233200 ] cPickle does not use Py_BEGIN_ALLOW_THREADS. http://sourceforge.net/tracker/?func=detail&aid=233200&group_id=5470&atid=1… Wrapped the fread/fwrite calls in thread BEGIN_ALLOW/END_ALLOW brackets Afraid I hit the "delete trailing whitespace key" too! Only two "real" sections of code changed here. ---------------------------- Lib/xml/sax/xmlreader.py, 1.13->1.14 Import the exceptions that this module can raise. ---------------------------- Lib/xmllib.py, 1.27->1.28 Moved clearing of "literal" flag. The flag is set in setliteral which can be called from a start tag handler. When the corresponding end tag is read the flag is cleared. However, it didn't get cleared when the start tag was for an empty element of the type <tag .../>. This modification fixes the problem. ---------------------------- Modules/pwdmodule.c, 1.24->1.25 Modules/grpmodule.c, 1.14->1.15 Make sure we close the group and password databases when we are done with them; this closes SF bug #407504. ---------------------------- Python/errors.c, 2.61->2.62 Objects/intobject.c, 2.55->2.56 Modules/timemodule.c, 2.107->2.108 Use Py_CHARMASK for ctype macros. Fixes bug #232787. ---------------------------- Modules/termios.c, 2.17->2.18 Add more protection around the VSWTC/VSWTCH, CRTSCTS, and XTABS symbols; these can be missing on some (all?) Irix and Tru64 versions. Protect the CRTSCTS value with a cast; this can be a larger value on Solaris/SPARC. This should fix SF tracker items #405092, #405350, and #405355. ---------------------------- Modules/pyexpat.c, 2.42->2.43 Wrap some long lines, use only C89 /* */ comments, and add spaces around some operators (style guide conformance). ---------------------------- Modules/termios.c, 2.15->2.16 Revised version of Jason Tishler's patch to make this compile on Cygwin, which does not define all the constants. This closes SF tracker patch #404924. ---------------------------- Modules/bsddbmodule.c, 1.27->1.28 Gustavo Niemeyer <niemeyer(a)conectiva.com>: Fixed recno support (keys are integers rather than strings). Work around DB bug that cause stdin to be closed by rnopen() when the DB file needed to exist but did not (no longer segfaults). This closes SF tracker patch #403445. Also wrapped some long lines and added whitespace around operators -- FLD. ---------------------------- Lib/urllib.py, 1.117->1.118 Fixing bug #227562 by calling URLopener.http_error_default when an invalid 401 request is being handled. ---------------------------- Python/compile.c, 2.170->2.171 Shuffle premature decref; nuke unreachable code block. Fixes the "debug-build -O test_builtin.py and no test_b2.pyo" crash just discussed on Python-Dev. ---------------------------- Python/import.c, 2.161->2.162 The code in PyImport_Import() tried to save itself a bit of work and save the __builtin__ module in a static variable. But this doesn't work across Py_Finalise()/Py_Initialize()! It also doesn't work when using multiple interpreter states created with PyInterpreterState_New(). So I'm ripping out this small optimization. This was probably broken since PyImport_Import() was introduced in 1997! We really need a better test suite for multiple interpreter states and repeatedly initializing. This fixes the problems Barry reported in Demo/embed/loop.c. ---------------------------- Modules/unicodedata.c, 2.9->2.11 renamed internal functions to avoid name clashes under OpenVMS (fixes bug #132815) ---------------------------- Modules/pyexpat.c, 2.40->2.41 Remove the old version of my_StartElementHandler(). This was conditionally compiled only for some versions of Expat, but was no longer needed as the new implementation works for all versions. Keeping it created multiple definitions for Expat 1.2, which caused compilation to fail. ---------------------------- Lib/urllib.py, 1.116->1.117 provide simple recovery/escape from apparent redirect recursion. If the number of entries into http_error_302 exceeds the value set for the maxtries attribute (which defaults to 10), the recursion is exited by calling the http_error_500 method (or if that is not defined, http_error_default). ---------------------------- Modules/posixmodule.c, 2.183->2.184 Add a few more missing prototypes to the SunOS 4.1.4 section (no SF bugreport, just an IRC one by Marion Delgado.) These prototypes are necessary because the functions are tossed around, not just called. ---------------------------- Modules/mpzmodule.c, 2.35->2.36 Richard Fish <rfish(a)users.sourceforge.net>: Fix the .binary() method of mpz objects for 64-bit systems. [Also removed a lot of trailing whitespace elsewhere in the file. --FLD] This closes SF patch #103547. ---------------------------- Python/pythonrun.c, 2.121->2.122 Ugly fix for SF bug 131239 (-x flag busted). Bug was introduced by tricks played to make .pyc files executable via cmdline arg. Then again, -x worked via a trick to begin with. If anyone can think of a portable way to test -x, be my guest! ---------------------------- Makefile.pre.in, 1.15->1.16 Specify directory permissions properly. Closes SF patch #103717. ---------------------------- install-sh, 2.3->2.4 Update install-sh using version from automake 1.4. Closes patch #103657 and #103717. ---------------------------- Modules/socketmodule.c, 1.135->1.136 Patch #103636: Allow writing strings containing null bytes to an SSL socket ---------------------------- Modules/mpzmodule.c, 2.34->2.35 Patch #103523, to make mpz module compile with Cygwin ---------------------------- Objects/floatobject.c, 2.78->2.79 SF patch 103543 from tg(a)freebsd.org: PyFPE_END_PROTECT() was called on undefined var ---------------------------- Modules/posixmodule.c, 2.181->2.182 Fix Bug #125891 - os.popen2,3 and 4 leaked file objects on Windows. ---------------------------- Python/ceval.c, 2.224->2.225 SF bug #130532: newest CVS won't build on AIX. Removed illegal redefinition of REPR macro; kept the one with the argument name that isn't too easy to confuse with zero <wink>. ---------------------------- Objects/classobject.c, 2.35->2.36 Rename dubiously named local variable 'cmpfunc' -- this is also a typedef, and at least one compiler choked on this. (SF patch #103457, by bquinlan) ---------------------------- Modules/_cursesmodule.c, 2.47->2.50 Patch #103485 from Donn Cave: patches to make the module compile on AIX and NetBSD Rename 'lines' variable to 'nlines' to avoid conflict with a macro defined in term.h 2001/01/28 18:10:23 akuchling Modules/_cursesmodule.c Bug #130117: add a prototype required to compile cleanly on IRIX (contributed by Paul Jackson) ---------------------------- Lib/statcache.py, 1.9->1.10 SF bug #130306: statcache.py full of thread problems. Fixed the thread races. Function forget_dir was also utterly Unix-specific. ---------------------------- Python/structmember.c, 1.74->1.75 SF bug http://sourceforge.net/bugs/?func=detailbug&bug_id=130242&group_id=5470 SF patch http://sourceforge.net/patch/?func=detailpatch&patch_id=103453&group_id=5470 PyMember_Set of T_CHAR always raises exception. Unfortunately, this is a use of a C API function that Python itself never makes, so there's no .py test I can check in to verify this stays fixed. But the fault in the code is obvious, and Dave Cole's patch just as obviously fixes it. ---------------------------- Modules/arraymodule.c, 2.61->2.62 Correct one-line typo, reported by yole @ SF, bug 130077. ---------------------------- Python/compile.c, 2.150->2.151 Fix bug reported by Ka-Ping Yee: The compiler botched parsing function parameters that contained both anonymous tuples and *arg or **arg. Ex: def f(a, (b, c), *d): pass Fix the symtable_params() to generate names in the right order for co_varnames slot of code object. Consider *arg and **arg before the "complex" names introduced by anonymous tuples. ---------------------------- Modules/config.c.in, 1.72->1.73 _PyImport_Inittab: define the exceptions module's init function. Fixes bug #121706. ---------------------------- Python/exceptions.c, 1.19->1.20 [Ed. -- only partial] Leak pluggin', bug fixin' and better documentin'. Specifically, module__doc__: Document the Warning subclass heirarchy. make_class(): Added a "goto finally" so that if populate_methods() fails, the return status will be -1 (failure) instead of 0 (success). fini_exceptions(): When decref'ing the static pointers to the exception classes, clear out their dictionaries too. This breaks a cycle from class->dict->method->class and allows the classes with unbound methods to be reclaimed. This plugs a large memory leak in a common Py_Initialize()/dosomething/Py_Finalize() loop. ---------------------------- Python/pythonrun.c, 2.118->2.119 Lib/atexit.py, 1.3->1.4 Bug #128475: mimetools.encode (sometimes) fails when called from a thread. pythonrun.c: In Py_Finalize, don't reset the initialized flag until after the exit funcs have run. atexit.py: in _run_exitfuncs, mutate the list of pending calls in a threadsafe way. This wasn't a contributor to bug 128475, it just burned my eyeballs when looking at that bug. ---------------------------- Modules/ucnhash.c, 1.6->1.7 gethash/cmpname both looked beyond the end of the character name. This patch makes u"\N{x}" a bit less dependent on pure luck... ---------------------------- Lib/urllib.py, 1.112->1.113 Anonymous SF bug 129288: "The python 2.0 urllib has %%%x as a format when quoting forbidden characters. There are scripts out there that break with lower case, therefore I guess %%%X should be used." I agree, so am fixing this. ---------------------------- Python/bltinmodule.c, 2.191->2.192 Fix for the bug in complex() just reported by Ping. ---------------------------- Modules/socketmodule.c, 1.130->1.131 Use openssl/*.h to include the OpenSSL header files ---------------------------- Lib/distutils/command/install.py, 1.55->1.56 Modified version of a patch from Jeremy Kloth, to make .get_outputs() produce a list of unique filenames: "While attempting to build an RPM using distutils on Python 2.0, rpm complained about duplicate files. The following patch fixed that problem. ---------------------------- Objects/unicodeobject.c, 2.72->2.73 Objects/stringobject.c, 2.96->2.97 (partial) Added checks to prevent PyUnicode_Count() from dumping core in case the parameters are out of bounds and fixes error handling for .count(), .startswith() and .endswith() for the case of mixed string/Unicode objects. This patch adds Python style index semantics to PyUnicode_Count() indices (including the special handling of negative indices). The patch is an extended version of patch #103249 submitted by Michael Hudson (mwh) on SF. It also includes new test cases. ---------------------------- Modules/posixmodule.c, 2.180->2.181 Plug memory leak. ---------------------------- Python/dynload_mac.c, 2.9->2.11 Use #if TARGET_API_MAC_CARBON to determine carbon/classic macos, not #ifdef. Added a separate extension (.carbon.slb) for Carbon dynamic modules. ---------------------------- Modules/mmapmodule.c, 2.26->2.27 SF bug 128713: type(mmap_object) blew up on Linux. ---------------------------- Python/sysmodule.c, 2.81->2.82 stdout is sometimes a macro; use "outf" instead. Submitted by: Mark Favas <m.favas(a)per.dem.csiro.au> ---------------------------- Python/ceval.c, 2.215->2.216 Add missing Py_DECREF in fast_cfunction. Partial fix for SF bug #127699. ---------------------------- Modules/mmapmodule.c, 2.24->2.25 Windows mmap should (as the docs probably <wink> say) create a mapping without a name when the optional tagname arg isn't specified. Was actually creating a mapping with an empty string as the name. ---------------------------- Lib/shlex.py, 1.10->1.11 Patch #102953: Fix bug #125452, where shlex.shlex hangs when it encounters a string with an unmatched quote, by adding a check for EOF in the 'quotes' state. ---------------------------- Modules/binascii.c, 2.27->2.28 Address a bug in the uuencode decoder, reported bu "donut" in SF bug #127718: '@' and '`' seem to be confused. ---------------------------- Objects/fileobject.c, 2.102->2.103 Tsk, tsk, tsk. Treat FreeBSD the same as the other BSDs when defining a fallback for TELL64. Fixes SF Bug #128119. ---------------------------- Modules/posixmodule.c, 2.179->2.180 Anonymous SF bug report #128053 point out that the #ifdef for including "tmpfile" in the posix_methods[] array is wrong -- should be HAVE_TMPFILE, not HAVE_TMPNAM. ---------------------------- Lib/urllib.py, 1.109->1.110 Fixed bug which caused HTTPS not to work at all with string URLs ---------------------------- Objects/floatobject.c, 2.76->2.77 Fix a silly bug in float_pow. Sorry Tim. ---------------------------- Modules/fpectlmodule.c, 2.12->2.13 Patch #103012: Update fpectlmodule for current glibc; The _setfpucw() function/macro doesn't seem to exist any more; instead there's an _FPU_SETCW macro. ---------------------------- Objects/dictobject.c, 2.71->2.72 dict_update has two boundary conditions: a.update(a) and a.update({}) Added test for second one. ---------------------------- Objects/listobject.c fix leak ---------------------------- Lib/getopt.py, 1.11->1.13 getopt used to sort the long option names, in an attempt to simplify the logic. That resulted in a bug. My previous getopt checkin repaired the bug but left the sorting. The solution is significantly simpler if we don't bother sorting at all, so this checkin gets rid of the sort and the code that relied on it. Fix for SF bug https://sourceforge.net/bugs/?func=detailbug&bug_id=126863&group_id=5470 "getopt long option handling broken". Tossed the excruciating logic in long_has_args in favor of something obviously correct. ---------------------------- Lib/curses/ascii.py, 1.3->1.4 Make isspace(chr(32)) return true ---------------------------- Lib/distutils/command/install.py, 1.54->1.55 Add forgotten initialization. Fixes bug #120994, "Traceback with DISTUTILS_DEBUG set" ---------------------------- Objects/unicodeobject.c, 2.68->2.69 Fix off-by-one error in split_substring(). Fixes SF bug #122162. ---------------------------- Modules/cPickle.c, 2.53->2.54 Lib/pickle.py, 1.40->1.41 Minimal fix for the complaints about pickling Unicode objects. (SF bugs #126161 and 123634). The solution doesn't use the unicode-escape encoding; that has other problems (it seems not 100% reversible). Rather, it transforms the input Unicode object slightly before encoding it using raw-unicode-escape, so that the decoding will reconstruct the original string: backslash and newline characters are translated into their \uXXXX counterparts. This is backwards incompatible for strings containing backslashes, but for some of those strings, the pickling was already broken. Note that SF bug #123634 complains specifically that cPickle fails to unpickle the pickle for u'' (the empty Unicode string) correctly. This was an off-by-one error in load_unicode(). XXX Ugliness: in order to do the modified raw-unicode-escape, I've cut-and-pasted a copy of PyUnicode_EncodeRawUnicodeEscape() into this file that also encodes '\\' and '\n'. It might be nice to migrate this into the Unicode implementation and give this encoding a new name ('half-raw-unicode-escape'? 'pickle-unicode-escape'?); that would help pickle.py too. But right now I can't be bothered with the necessary infrastructural changes. ---------------------------- Modules/socketmodule.c, 1.129->1.130 Adapted from a patch by Barry Scott, SF patch #102875 and SF bug #125981: closing sockets was not thread-safe. ---------------------------- Lib/xml/dom/__init__.py, 1.4->1.6 Typo caught by /F -- thanks! DOMException.__init__(): Remember to pass self to Exception.__init__(). ---------------------------- Lib/urllib.py, 1.108->1.09 (partial) Get rid of string functions, except maketrans() (which is *not* obsolete!). Fix a bug in ftpwrapper.retrfile() where somehow ftplib.error_perm was assumed to be a string. (The fix applies str().) Also break some long lines and change the output from test() slightly. ---------------------------- Modules/bsddbmodule.c, 1.25->1.26 [Patch #102827] Fix for PR#119558, avoiding core dumps by checking for malloc() returning NULL ---------------------------- Lib/site.py, 1.21->1.22 The ".pth" code knew about the layout of Python trees on unix and windows, but not on the mac. Fixed. ---------------------------- Modules/selectmodule.c, 1.83->1.84 SF bug 110843: Low FD_SETSIZE limit on Win32 (PR#41). Boosted to 512. ---------------------------- Modules/parsermodule.c, 2.58->2.59 validate_varargslist(): Fix two bugs in this function, one that affected it when *args and/or **kw are used, and one when they are not. This closes bug #125375: "parser.tuple2ast() failure on valid parse tree". ---------------------------- Lib/httplib.py, 1.24->1.25 Hoepeful fix for SF bug #123924: Windows - using OpenSSL, problem with socket in httplib.py. The bug reports that on Windows, you must pass sock._sock to the socket.ssl() call. But on Unix, you must pass sock itself. (sock is a wrapper on Windows but not on Unix; the ssl() call wants the real socket object, not the wrapper.) So we see if sock has an _sock attribute and if so, extract it. Unfortunately, the submitter of the bug didn't confirm that this patch works, so I'll just have to believe it (can't test it myself since I don't have OpenSSL on Windows set up, and that's a nontrivial thing I believe). ---------------------------- Python/getargs.c, 2.50->2.51 vgetargskeywords(): Patch for memory leak identified in bug #119862. ---------------------------- Lib/ConfigParser.py, 1.23->1.24 remove_option(): Use the right variable name for the option name! This closes bug #124324. ---------------------------- Lib/filecmp.py, 1.6->1.7 Call of _cmp had wrong number of paramereters. Fixed definition of _cmp. ---------------------------- Python/compile.c, 2.143->2.144 Plug a memory leak in com_import_stmt(): the tuple created to hold the "..." in "from M import ..." was never DECREFed. Leak reported by James Slaughter and nailed by Barry, who also provided an earlier version of this patch. ---------------------------- Objects/stringobject.c, 2.92->2.93 SF patch #102548, fix for bug #121013, by mwh(a)users.sourceforge.net. Fixes a typo that caused "".join(u"this is a test") to dump core. ---------------------------- Python/marshal.c, 1.57->1.58 Python/compile.c, 2.142->2.143 SF bug 119622: compile errors due to redundant atof decls. I don't understand the bug report (for details, look at it), but agree there's no need for Python to declare atof itself: we #include stdlib.h, and ANSI C sez atof is declared there already. ---------------------------- Lib/webbrowser.py, 1.4->1.5 Typo for Mac code, fixing SF bug 12195. ---------------------------- Objects/fileobject.c, 2.91->2.92 Added _HAVE_BSDI and __APPLE__ to the list of platforms that require a hack for TELL64()... Sounds like there's something else going on really. Does anybody have a clue I can buy? ---------------------------- Python/thread_cthread.h, 2.13->2.14 Fix syntax error. Submitted by Bill Bumgarner. Apparently this is still in use, for Apple Mac OSX. ---------------------------- Modules/arraymodule.c, 2.58->2.59 Fix for SF bug 117402, crashes on str(array) and repr(array). This was an unfortunate consequence of somebody switching from PyArg_Parse to PyArg_ParseTuple but without changing the argument from a NULL to a tuple. ---------------------------- Lib/smtplib.py, 1.29->1.30 SMTP.connect(): If the socket.connect() raises a socket.error, be sure to call self.close() to reclaim some file descriptors, the reraise the exception. Closes SF patch #102185 and SF bug #119833. ---------------------------- Objects/rangeobject.c, 2.20->2.22 Fixed support for containment test when a negative step is used; this *really* closes bug #121965. Added three attributes to the xrange object: start, stop, and step. These are the same as for the slice objects. In the containment test, get the boundary condition right. ">" was used where ">=" should have been. This closes bug #121965. ---------------------------- configure.in, 1.177->1.178 Fix for SF bug #117606: - when compiling with GCC on Solaris, use "$(CC) -shared" instead of "$(CC) -G" to generate .so files - when compiling with GCC on any platform, add "-fPIC" to OPT (without this, "$(CC) -shared" dies horribly) ---------------------------- configure.in, 1.175->1.176 Make sure the Modules/ directory is created before writing Modules/Setup. ---------------------------- Modules/_cursesmodule.c, 2.39->2.40 Patch from Randall Hopper to fix PR #116172, "curses module fails to build on SGI": * Check for 'sgi' preprocessor symbol, not '__sgi__' * Surround individual character macros with #ifdef's, instead of making them all rely on STRICT_SYSV_CURSES ---------------------------- Modules/_tkinter.c, 1.114->1.115 Do not release unallocated Tcl objects. Closes #117278 and #117167. ---------------------------- Python/dynload_shlib.c, 2.6->2.7 Patch 102114, Bug 11725. On OpenBSD (but apparently not on the other BSDs) you need a leading underscore in the dlsym() lookup name. ---------------------------- Lib/UserString.py, 1.6->1.7 Fix two typos in __imul__. Closes Bug #117745. ---------------------------- Lib/mailbox.py, 1.25->1.26 Maildir.__init__(): Make sure self.boxes is set. This closes SourceForge bug #117490. ---------------------------- -- "I'll be ex-DPL soon anyway so I'm |LUKE: Is Perl better than Python? looking for someplace else to grab power."|YODA: No...no... no. Quicker, -- Wichert Akkerman (on debian-private)| easier, more seductive. For public key, finger moshez(a)debian.org |http://www.{python,debian,gnu}.org

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'mapping' in weakrefs unneeded?
by Andrew Dalke 29 Mar '01

29 Mar '01

Hello all, I'm starting to learn how to use weakrefs. I'm curious about the function named 'mapping'. It is implemented as: > def mapping(dict=None,weakkeys=0): > if weakkeys: > return WeakKeyDictionary(dict) > else: > return WeakValueDictionary(dict) Why is this a useful function? Shouldn't people just call WeakKeyDictionary and WeakValueDictionary directly instead of calling mapping with a parameter to specify which class to construct? If anything, this function is very confusing. Take the associated documentation as a case in point: > mapping([dict[, weakkeys=0]]) > Return a weak dictionary. If dict is given and not None, > the new dictionary will contain the items contained in dict. > The values from dict must be weakly referencable; if any > values which would be inserted into the new mapping are not > weakly referencable, TypeError will be raised and the new > mapping will be empty. > > If the weakkeys argument is not given or zero, the values in > the dictionary are weak. That means the entries in the > dictionary will be discarded when no strong reference to the > value exists anymore. > > If the weakkeys argument is nonzero, the keys in the > dictionary are weak, i.e. the entry in the dictionary is > discarded when the last strong reference to the key is > discarded. As far as I can tell, this documentation is wrong, or at the very least confusing. For example, it says: > The values from dict must be weakly referencable but when the weakkeys argument is nonzero, > the keys in the dictionary are weak So must both keys and values be weak? Or only the keys? I hope the latter since there are cases I can think of where I want the keys to be weak and the values be types, hence non-weakreferencable. Wouldn't it be better to remove the 'mapping' function and only have the WeakKeyDictionary and WeakValueDictionary. In which case the documentation becomes: > WeakValueDictionary([dict]) > Return a weak dictionary. If dict is given and not None, > the new dictionary will contain the items contained in dict. > The values from dict must be weakly referencable; if any > values which would be inserted into the new mapping are not > weakly referencable, TypeError will be raised and the new > mapping will be empty. > > The values in > the dictionary are weak. That means the entries in the > dictionary will be discarded when no strong reference to the > value exists anymore. > WeakKeyDictionary([dict]) > Return a weak dictionary. If dict is given and not None, > the new dictionary will contain the items contained in dict. > The keys from dict must be weakly referencable; if any > keys which would be inserted into the new mapping are not > weakly referencable, TypeError will be raised and the new > mapping will be empty. > > The keys in > the dictionary are weak. That means the entries in the > dictionary will be discarded when no strong reference to the > key exists anymore. Easier to read and to see the parallels between the two styles, IMHO of course. I am not on this list though I will try to read the archives online for the next couple of days. Please CC me about any resolution to this topic. Sincerely, Andrew dalke(a)acm.org

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[development doc updates]
by fdrake＠cj42289-a.reston1.va.home.com 29 Mar '01

29 Mar '01

The development version of the documentation has been updated: http://python.sourceforge.net/devel-docs/ For Peter Funk: Removed space between function/method/class names and their parameter lists for easier cut & paste. This is a *tentative* change; feedback is appreciated at python-docs(a)python.org. Also added some new information on integrating with the cycle detector and some additional C APIs introduced in Python 2.1 (PyObject_IsInstance(), PyObject_IsSubclass()).

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python-dev summary, 2001-03-15 - 2001-03-29
by Michael Hudson 29 Mar '01

29 Mar '01

This is a summary of traffic on the python-dev mailing list between Mar 15 and Mar 28 (inclusive) 2001. It is intended to inform the wider Python community of ongoing developments. To comment, just post to python-list(a)python.org or comp.lang.python in the usual way. Give your posting a meaningful subject line, and if it's about a PEP, include the PEP number (e.g. Subject: PEP 201 - Lockstep iteration) All python-dev members are interested in seeing ideas discussed by the community, so don't hesitate to take a stance on a PEP if you have an opinion. This is the fourth summary written by Michael Hudson. Summaries are archived at: <http://starship.python.net/crew/mwh/summaries/> Posting distribution (with apologies to mbm) Number of articles in summary: 410 50 | [|] | [|] | [|] | [|] 40 | [|] | [|] [|] | [|] [|] [|] | [|] [|] [|] [|] [|] 30 | [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] 20 | [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] 10 | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] | [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] [|] 0 +-044-024-013-029-059-046-040-022-040-031-007-019-008-028 Thu 15| Sat 17| Mon 19| Wed 21| Fri 23| Sun 25| Tue 27| Fri 16 Sun 18 Tue 20 Thu 22 Sat 24 Mon 26 Wed 28 Bug-fixing for 2.1 remained a priority for python-dev this fortnight which saw the release of 2.1b2 last Friday. * Python 2.0.1 * Aahz posted his first draft of PEP 6, outlining the process by which maintenance releases of Python should be made. <http://python.sourceforge.net/peps/pep-0006.html> Moshe Zadka has volunteered to be the "Patch Czar" for Python 2.0.1. <http://mail.python.org/pipermail/python-dev/2001-March/013952.html> I'm sure we can all join in the thanks due to Moshe for taking up this tedious but valuable job! * Simple Generator implementations * Neil Schemenauer posted links to a couple of "simple" implementations of generators (a.k.a. resumable functions) that do not depend on the stackless changes going in. <http://mail.python.org/pipermail/python-dev/2001-March/013648.html> <http://mail.python.org/pipermail/python-dev/2001-March/013666.html> These implementations have the advantage that they might be applicable to Jython, something that sadly cannot be said of stackless. * portable file-system stuff * The longest thread of the summary period started off with a request for a portable way to find out free disk space: <http://mail.python.org/pipermail/python-dev/2001-March/013706.html> After a slightly acrimonious debate about the nature of Python development, /F produced a patch that implements partial support for os.statvfs on Windows: <http://sourceforge.net/tracker/index.php?func=detail&aid=410547&group_id=54…> which can be used to extract such information. A side-product of this discussion was the observation that although Python has a module that does some file manipulation, shutil, it is far from being as portable as it might be - in particular it fails miserably on the Mac where it ignores resource forks. Greg Ward then pointed out that he had to implement cross-platform file copying for the distutils <http://mail.python.org/pipermail/python-dev/2001-March/013962.html> so perhaps all that needs to be done is for this stuff to be moved into the core. It seems very unlikely there will be much movement here before 2.2.

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Re: [Python-Dev] test_doctest failing, but perhaps by accident
by Michael Hudson 28 Mar '01

28 Mar '01

"Tim Peters" <tim.one(a)home.com> writes: > I'm calling this one a bug in doctest.py, and will fix it there. Ugly: > since we can longer rely on list.sort() not raising exceptions, it won't be > enough to replace the existing > > for k, v in dict.items(): > > with > > items = dict.items() > items.sort() > for k, v in items: Hmm, reading through these posts for summary purposes, it occurs to me that this *is* safe, 'cause item 0 of the tuples will always be distinct strings, and as equal-length tuples are compared lexicographically, the values will never actually be compared! pointless-ly y'rs M. -- 93. When someone says "I want a programming language in which I need only say what I wish done," give him a lollipop. -- Alan Perlis, http://www.cs.yale.edu/homes/perlis-alan/quotes.html

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Updated, shorter PEP 245
by Michel Pelletier 28 Mar '01

28 Mar '01

Hi folks, I have broken PEP 245 into two different PEPs, the first, which is now PEP 245, covers only the syntax and the changes to the Python language. It is much shorter and sweeter that the old one. The second one, yet to have a number or to be totally polished off, describes my proposed interface *model* based on the Zope interfaces work and the previous incarnation of PEP 245. This next PEP is totally independent of PEP 245, and can be accepted or rejected independent of the syntax if a different model is desired. In fact, Amos Latteier has proposed to me a different, simpler, though less functional model that would make an excellent alternative. I'll encourage him to formalize it. Or would it be acceptable to offer two possible models in the same PEP? Finally, I forsee a third PEP to cover issues beyond the model, like type checking, interface enforcement, and formalizing well-known python "protocols" as interfaces. That's a work for later consideration, that is also independent of the previous two PEPs. The *new* PEP 245 can be found at the following link: http://www.zope.org/Members/michel/MyWiki/InterfacesPEP/PEP245.txt Enjoy, and please feel free to comment. -Michel

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List of Patches to Go in 2.0.1
by Martin v. Loewis 28 Mar '01

28 Mar '01

> Modules/_tkinter.c, 1.114->1.115 > Do not release unallocated Tcl objects. Closes #117278 and #117167. That is already committed to the maintenance branch. > Modules/pyexpat.c, 2.42->2.43 There is a number of memory leaks which I think should get fixed, inside the changes: 2.33->2.34 2.31->2.32 (garbage collection, and missing free calls) I can produce a patch that only has those changes. Martin

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List of Patches to Go in 2.0.1
by Martin v. Loewis 28 Mar '01

28 Mar '01

> This one Aahz singled out previously as a canonical example of a patch he > would *not* include, because adding new attributes seemed potentially > disruptive to him (but why? maybe someone was depending on the precise value > of len(dir(xrange(42)))?). There is a patch on SF which backports that change without introducing these attributes in the 2.0.1 class. Regards, Martin

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MacPython 2.1b2 available
by jack＠oratrix.nl 28 Mar '01

28 Mar '01

MacPython 2.1b2 is available for download. Get it via http://www.cwi.nl/~jack/macpython.html . New in this version: - A choice of Carbon or Classic runtime, so runs on anything between MacOS 8.1 and MacOS X - Distutils support for easy installation of extension packages - BBedit language plugin - All the platform-independent Python 2.1 mods - New version of Numeric - Lots of bug fixes - Choice of normal and active installer Please send feedback on this release to pythonmac-sig(a)python.org, where all the maccies hang out. Enjoy, -- Jack Jansen | ++++ stop the execution of Mumia Abu-Jamal ++++ Jack.Jansen(a)oratrix.com | ++++ if you agree copy these lines to your sig ++++ www.oratrix.nl/~jack | ++++ see http://www.xs4all.nl/~tank/ ++++

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