Mailman 3 September 2011 - Python-Dev

Unicode identifiers
by Egon Smiwa 20 Sep '11

20 Sep '11

Hi all, I wanted to implement quantity objects in a software, which can be used with user-friendly expressions like: money = 3 * €, where Euro is a special quantity object But now I realized, Python does not allow currency characters in names, although they can be very useful. Is there a really convincing argument against the inclusion? Thank you!

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Persistent Python - a la Smalltalk
by Albert Zeyer 18 Sep '11

18 Sep '11

Hi, I was thinking about a persistent Python interpreter system. I.e. you start a Python interpreter instance and you load and create all your objects, classes and code in there (or load it in there from other files). The basic idea is that you wont restart your Python script, you would always modify it on-the-fly. Or a bit less extreme: You would at least have the possibility with this to do this (like just doing minor changes). Also, if your PC halts for whatever reason, you can continue your Python script after a restart. This goes along my other recent proposal to store the AST of statements in the related code objects (http://thread.gmane.org/gmane.comp.python.devel/126754). An internal editor could then edit this AST and recompile the code object. For the persistance, there would be an image file containing all the Python objects. All in all, much like most Smalltalk systems. --- Has anyone done something like this already? --- There are a few implementation details which are not trivial and there doesn't seem to be straight forward solutions, e.g. most generally: * How to implement the persistance? * How to handle image compatibility between CPython updates? Even possible? Regards, Albert

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Re: [Python-Dev] Persistent Python - a la Smalltalk
by Zbigniew Jędrzejewski-Szmek 18 Sep '11

18 Sep '11

Guido van Rossum wrote: > [BCC python-dev, +python-ideas] > > Funny you should mention this. ABC, Python's predecessor, worked like > this. However, it didn't work out very well. So, I'd say you're about > 30 years too late with your idea... :-( Well, the newly developed IPython notebook [1] is something along those lines. So he's not late, he's a little bit early :) -- Zbyszek http://ipython.org/ipython-doc/dev/interactive/htmlnotebook.html

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Summary of Python tracker Issues
by Python tracker 16 Sep '11

16 Sep '11

ACTIVITY SUMMARY (2011-09-09 - 2011-09-16) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open 3019 (+19) closed 21757 (+30) total 24776 (+49) Open issues with patches: 1295 Issues opened (36) ================== #12946: PyModule_GetDict() claims it can never fail, but it can http://bugs.python.org/issue12946 opened by scoder #12949: Documentation of PyCode_New() lacks kwonlyargcount argument http://bugs.python.org/issue12949 opened by scoder #12953: Function calls missing from profiler output http://bugs.python.org/issue12953 opened by hagen #12954: Multiprocessing logging under Windows http://bugs.python.org/issue12954 opened by paul.j3 #12955: urllib2.build_opener().open() is not friendly to "with ... as: http://bugs.python.org/issue12955 opened by Valery.Khamenya #12956: builds fail when installing to --prefix with space in path nam http://bugs.python.org/issue12956 opened by rzn8tr #12957: mmap.resize changes memory address of mmap'd region http://bugs.python.org/issue12957 opened by schmichael #12958: test_socket failures on Mac OS X http://bugs.python.org/issue12958 opened by ncoghlan #12960: threading.Condition is not a class http://bugs.python.org/issue12960 opened by Nikratio #12961: unlabelled balls in boxes http://bugs.python.org/issue12961 opened by Phillip.M.Feldman #12962: TitledHelpFormatter and IndentedHelpFormatter are not document http://bugs.python.org/issue12962 opened by techtonik #12964: Two improvements for the locale aliasing engine http://bugs.python.org/issue12964 opened by ssegvic #12965: longobject: documentation improvements http://bugs.python.org/issue12965 opened by skrah #12966: cookielib.LWPCookieJar breaks on cookie values with a newline http://bugs.python.org/issue12966 opened by paulie4 #12967: AttributeError distutils\log.py http://bugs.python.org/issue12967 opened by Ben.thelen #12970: os.walk() consider some symlinks as dirs instead of non-dirs http://bugs.python.org/issue12970 opened by mmarkk #12971: os.isdir() should contain skiplinks=False in arguments http://bugs.python.org/issue12971 opened by mmarkk #12972: Color prompt + readline http://bugs.python.org/issue12972 opened by atagar1 #12973: int_pow() implementation is incorrect http://bugs.python.org/issue12973 opened by adam(a)NetBSD.org #12974: array module: deprecate '__int__' conversion support for array http://bugs.python.org/issue12974 opened by meadori #12976: select module: only use EVFILT_TIMER if available (kqueue back http://bugs.python.org/issue12976 opened by bsiegert #12977: socket.socket.setblocking does not raise exception if no data http://bugs.python.org/issue12977 opened by Florian.Ludwig #12978: Figure out extended attributes on BSDs http://bugs.python.org/issue12978 opened by benjamin.peterson #12979: tkinter.font.Font object not usable as font option http://bugs.python.org/issue12979 opened by ilikepython #12981: rewrite multiprocessing (senfd|recvfd) in Python http://bugs.python.org/issue12981 opened by neologix #12982: .pyo file cannot be imported http://bugs.python.org/issue12982 opened by lebigot #12983: byte string literals with invalid hex escape codes raise Value http://bugs.python.org/issue12983 opened by ned.deily #12984: XML NamedNodeMap ( attribName in NamedNodeMap fails ) http://bugs.python.org/issue12984 opened by spolematt #12985: Check signed arithmetic overflow in ./configure http://bugs.python.org/issue12985 opened by skrah #12986: Using getrandbits() in uuid.uuid4() is faster and more readabl http://bugs.python.org/issue12986 opened by mattchaput #12987: Demo/scripts/newslist.py has non-commercial license clause http://bugs.python.org/issue12987 opened by matejcik #12988: IDLE on Win7 crashes when saving to Documents Library http://bugs.python.org/issue12988 opened by Brian.Gernhardt #12989: Consistently handle path separator in Py_GetPath on Windows http://bugs.python.org/issue12989 opened by Nam.Nguyen #12990: launcher can't work on path including tradition chinese char http://bugs.python.org/issue12990 opened by Ricky.Teng #12993: prepared statements in sqlite3 module http://bugs.python.org/issue12993 opened by Mayur.&.Angela.Patel-Lam #12994: cx_Oracle failed to load in newly build python 2.7.1 http://bugs.python.org/issue12994 opened by wah meng Most recent 15 issues with no replies (15) ========================================== #12994: cx_Oracle failed to load in newly build python 2.7.1 http://bugs.python.org/issue12994 #12993: prepared statements in sqlite3 module http://bugs.python.org/issue12993 #12990: launcher can't work on path including tradition chinese char http://bugs.python.org/issue12990 #12989: Consistently handle path separator in Py_GetPath on Windows http://bugs.python.org/issue12989 #12988: IDLE on Win7 crashes when saving to Documents Library http://bugs.python.org/issue12988 #12987: Demo/scripts/newslist.py has non-commercial license clause http://bugs.python.org/issue12987 #12986: Using getrandbits() in uuid.uuid4() is faster and more readabl http://bugs.python.org/issue12986 #12984: XML NamedNodeMap ( attribName in NamedNodeMap fails ) http://bugs.python.org/issue12984 #12983: byte string literals with invalid hex escape codes raise Value http://bugs.python.org/issue12983 #12979: tkinter.font.Font object not usable as font option http://bugs.python.org/issue12979 #12977: socket.socket.setblocking does not raise exception if no data http://bugs.python.org/issue12977 #12972: Color prompt + readline http://bugs.python.org/issue12972 #12971: os.isdir() should contain skiplinks=False in arguments http://bugs.python.org/issue12971 #12966: cookielib.LWPCookieJar breaks on cookie values with a newline http://bugs.python.org/issue12966 #12965: longobject: documentation improvements http://bugs.python.org/issue12965 Most recent 15 issues waiting for review (15) ============================================= #12989: Consistently handle path separator in Py_GetPath on Windows http://bugs.python.org/issue12989 #12986: Using getrandbits() in uuid.uuid4() is faster and more readabl http://bugs.python.org/issue12986 #12985: Check signed arithmetic overflow in ./configure http://bugs.python.org/issue12985 #12981: rewrite multiprocessing (senfd|recvfd) in Python http://bugs.python.org/issue12981 #12973: int_pow() implementation is incorrect http://bugs.python.org/issue12973 #12970: os.walk() consider some symlinks as dirs instead of non-dirs http://bugs.python.org/issue12970 #12965: longobject: documentation improvements http://bugs.python.org/issue12965 #12943: tokenize: add python -m tokenize support back http://bugs.python.org/issue12943 #12936: armv5tejl segfaults: sched_setaffinity() vs. pthread_setaffini http://bugs.python.org/issue12936 #12931: xmlrpclib confuses unicode and string http://bugs.python.org/issue12931 #12930: reindent.py inserts spaces in multiline literals http://bugs.python.org/issue12930 #12919: Control what module is imported first http://bugs.python.org/issue12919 #12911: Expose a private accumulator C API http://bugs.python.org/issue12911 #12903: test_io.test_interrupte[r]d* blocks on OpenBSD http://bugs.python.org/issue12903 #12901: Nest class/methods directives in documentation http://bugs.python.org/issue12901 Top 10 most discussed issues (10) ================================= #12936: armv5tejl segfaults: sched_setaffinity() vs. pthread_setaffini http://bugs.python.org/issue12936 26 msgs #11457: Expose nanosecond precision from system calls http://bugs.python.org/issue11457 17 msgs #12973: int_pow() implementation is incorrect http://bugs.python.org/issue12973 16 msgs #1172711: long long support for array module http://bugs.python.org/issue1172711 11 msgs #8822: datetime naive and aware types should have a well-defined defi http://bugs.python.org/issue8822 10 msgs #12301: Use :role:`sys.thing` instead of ``sys.thing`` throughout http://bugs.python.org/issue12301 7 msgs #12945: ctypes works incorrectly with _swappedbytes_ = 1 http://bugs.python.org/issue12945 7 msgs #6715: xz compressor support http://bugs.python.org/issue6715 6 msgs #12913: Add a debugging howto http://bugs.python.org/issue12913 6 msgs #12981: rewrite multiprocessing (senfd|recvfd) in Python http://bugs.python.org/issue12981 6 msgs Issues closed (27) ================== #7201: double Endian problem and more on arm http://bugs.python.org/issue7201 closed by mark.dickinson #9871: IDLE 3 crashes processing byte strings with invalid hex escape http://bugs.python.org/issue9871 closed by ned.deily #11149: [PATCH] Configure should enable -fwrapv for clang http://bugs.python.org/issue11149 closed by skrah #12299: Stop documenting functions added by site as builtins http://bugs.python.org/issue12299 closed by eric.araujo #12306: zlib: Expose zlibVersion to query runtime version of zlib http://bugs.python.org/issue12306 closed by nadeem.vawda #12483: CThunkObject_dealloc should call PyObject_GC_UnTrack? http://bugs.python.org/issue12483 closed by meadori #12896: Recommended location of the interpreter for Python 3 http://bugs.python.org/issue12896 closed by eric.araujo #12914: Add cram function to textwrap http://bugs.python.org/issue12914 closed by rhettinger #12917: Make visiblename and allmethods functions public http://bugs.python.org/issue12917 closed by rhettinger #12918: New module for terminal utilities http://bugs.python.org/issue12918 closed by eric.araujo #12924: Missing call to quote_plus() in test_urllib.test_default_quoti http://bugs.python.org/issue12924 closed by python-dev #12935: Typo in findertools.py http://bugs.python.org/issue12935 closed by ned.deily #12940: Cmd example using turtle left vs. right doc-bug http://bugs.python.org/issue12940 closed by ezio.melotti #12941: add random.pop() http://bugs.python.org/issue12941 closed by terry.reedy #12947: Examples in library/doctest.html lack the flags http://bugs.python.org/issue12947 closed by eric.araujo #12948: multiprocessing test failures can hang the buildbots http://bugs.python.org/issue12948 closed by jcea #12950: multiprocessing "test_fd_transfer" fails under OpenIndiana http://bugs.python.org/issue12950 closed by python-dev #12951: List behavior is different http://bugs.python.org/issue12951 closed by ezio.melotti #12952: Solaris/Illumos (OpenIndiana) Scheduling policies http://bugs.python.org/issue12952 closed by python-dev #12959: Add 'ChainMap' to collections.__all__ http://bugs.python.org/issue12959 closed by python-dev #12963: PyLong_AsSize_t returns (unsigned long)-1 http://bugs.python.org/issue12963 closed by skrah #12968: vvccc留查！！！ http://bugs.python.org/issue12968 closed by benjamin.peterson #12969: Command 'open(0,"wb").close()' cause crash of Python interpret http://bugs.python.org/issue12969 closed by jcea #12975: spam http://bugs.python.org/issue12975 closed by neologix #12980: segfault in test_json on AMD64 FreeBSD 8.2 2.7 http://bugs.python.org/issue12980 closed by skrah #12991: Python 64-bit build on HP Itanium - Executable built successfu http://bugs.python.org/issue12991 closed by skrah #12992: Python build finished, but the necessary bits to build these m http://bugs.python.org/issue12992 closed by ezio.melotti

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PEP 393: Special-casing ASCII-only strings
by "Martin v. Löwis" 16 Sep '11

16 Sep '11

In reviewing memory usage, I found potential for saving more memory for ASCII-only strings. Both Victor and Guido commented that something like this be done; Antoine had asked whether there was anything that could be done. Here is the idea: In an ASCII-only string, the UTF-8 representation is shared with the canonical one-byte representation. This would allow to drop the UTF-8 pointer and the UTF-8 length field; instead, a flag in the state would indicate that these fields are not there. Likewise, the wchar_t/Py_UNICODE length can be shared (even though the data cannot), since the ASCII-only string won't contain any surrogate pairs. To comply with the C aliasing rules, the structures would look like this: typedef struct { PyObject_HEAD Py_ssize_t length; union { void *any; Py_UCS1 *latin1; Py_UCS2 *ucs2; Py_UCS4 *ucs4; } data; Py_hash_t hash; int state; /* may include SSTATE_SHORT_ASCII flag */ wchar_t *wstr; } PyASCIIObject; typedef struct { PyASCIIObject _base; Py_ssize_t utf8_length; char *utf8; Py_ssize_t wstr_length; } PyUnicodeObject; Code that directly accesses the structures would become more complex; code that use the accessor macros wouldn't notice. As a result, ASCII-only strings would lose three pointers, and shrink to their 3.2 structure size. Since they also save in the individual characters, strings with more than 3 characters (16-bit Py_UNICODE) or more than one character (32-bit Py_UNICODE) would see a total size reduction compared to 3.2. Objects created throught the legacy API (PyUnicode_FromUnicode) that are only later found to be ASCII-only (in PyUnicode_Ready) would still have the UTF-8 pointer shared with the data pointer, but keep including separate fields for pointer & size. What do you think? Regards, Martin P.S. There are similar reductions that could be applied to the wstr_length in general: on 32-bit wchar_t systems, it could be always dropped, on a 16-bit wchar_t system, it could be dropped for UCS-2 strings. However, I'm not proposing these, as I think the increase in complexity is not worth the savings.

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Meta coding in Python
by Albert Zeyer 15 Sep '11

15 Sep '11

Hi list, I thought it would be nice in Python to allow some sort of meta coding (which goes far ahead of simple function descriptors). The most straight forward way would be to allow operations on the AST. I wrote a small patch for CPython 2.7.1 which, for each code object, adds the related AST of the statement to a new attribute `co_ast`. https://github.com/albertz/CPython/commit/2670e621458fd80311fc02897b698ea2a… Some simple demonstration of what you can do with this: https://github.com/albertz/CPython/blob/astcompile_patch/test_co_ast.py I'm not sure wether the Python AST in this form is optimal for doing such things, though. Maybe another representation would be more efficient and result in simpler code for doing transformations. Discussion about this is very welcome. Regards, Albert

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Do we have interest in a clang buildbot?
by Jesus Cea 15 Sep '11

15 Sep '11

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, pals. I am seeing a few commits related to clang (a C compiler, alternative to GCC), but we ¿only? have a buildbot using clang as the compiler. If there is interest, I would deploy 32 and 64 bits buildbots under my current OpenIndiana buildbot. What do you think? - -- Jesus Cea Avion _/_/ _/_/_/ _/_/_/ jcea(a)jcea.es - http://www.jcea.es/ _/_/ _/_/ _/_/ _/_/ _/_/ jabber / xmpp:jcea@jabber.org _/_/ _/_/ _/_/_/_/_/ . _/_/ _/_/ _/_/ _/_/ _/_/ "Things are not so easy" _/_/ _/_/ _/_/ _/_/ _/_/ _/_/ "My name is Dump, Core Dump" _/_/_/ _/_/_/ _/_/ _/_/ "El amor es poner tu felicidad en la felicidad de otro" - Leibniz -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQCVAwUBTnHhl5lgi5GaxT1NAQKlJgQApAwlZODoeG3G+HODkoSh6G5myqEXkS/0 YZM6wo+/uWb6ul50Kb9mWhucGhY1tc8wAxCDNsRcm8Vv/6sDLZOV0G++DIK0JXIw BA8TyF/5CI8c5K3wnrVkazTo/Io1kVYMGc1FekIoQFI3oRKdXs/A6h63XWwxDMNu PsGwVD4bizs= =lJ/r -----END PGP SIGNATURE-----

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PEP 393: Porting Guidelines
by "Martin v. Löwis" 15 Sep '11

15 Sep '11

I added a section on porting guidelines to the PEP, resulting from my own porting experience. Please review. http://www.python.org/dev/peps/pep-0393/#porting-guidelines Regards, Martin

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LZMA compression support in 3.3
by Nadeem Vawda 15 Sep '11

15 Sep '11

Hello all, I'd like to propose the addition of a new module in Python 3.3. The 'lzma' module will provide support for compression and decompression using the LZMA algorithm, and the .xz and .lzma file formats. The matter has already been discussed on the tracker <http://bugs.python.org/issue6715>, where there seems to be a consensus that this is a desirable feature. What are your thoughts? The proposed module's API will be very similar to that of the bz2 module; the only differences will be additional keyword arguments to some functions, for specifying container formats and detailed compressor options. The implementation will also be similar to bz2 - basic compressor and decompressor classes written in C, with convenience functions and a file interface implemented on top of those in Python. I've already done some work on the C parts of the module; I'll push that to my sandbox <http://hg.python.org/sandbox/nvawda/> in the next day or two. Cheers, Nadeem

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Not able to do unregister a code
by Jai Sharma 15 Sep '11

15 Sep '11

Hi, I am facing a memory leaking issue with codecs. I make my own ABC class and register it with codes. import codecs codecs.register(ABC) but I am not able to remove ABC from memory. Is there any alternative to do that. Thanks

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