Mailman 3 February 2003 - Python-Dev

tuning up...
by Andrew MacIntyre 24 Feb '03

24 Feb '03

I've just put together a binary distribution of 2.3a2 for OS/2 EMX, and for the hell of it compared the pystone ratings of 2.3a2 against 2.2.2 on 2 different systems. Results: 2.2.2 2.3a2 change system 1 18200 21700 +19.2% system 2a 5600 6975 +24.5% system 2b 6600 8540 +29.4% (Pystone on 2.2.2 adjusted to 50000 loops, average of 3 runs) Hardware: system 1: Athlon 1.4GHz, 512MB (PC133), OS/2 v4.0 FP12, gcc 2.8.1 -O2 system 2a: Via C3 800MHz, 256MB (PC133), OS/2 v4.0 FP15, gcc 2.8.1 -O2 system 2b: " , " , FreeBSD 4.7, gcc 2.95.4 -g -O3 -- Andrew I MacIntyre "These thoughts are mine alone..." E-mail: andymac(a)bullseye.apana.org.au | Snail: PO Box 370 andymac(a)pcug.org.au | Belconnen ACT 2616 Web: http://www.andymac.org/ | Australia

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assymetry in descriptor behavior
by David Abrahams 24 Feb '03

24 Feb '03

In trying to support user requests for C++-like behavior of wrapped static data members, I noticed the following little assymetry: >>> #define a property class ... class Prop(object): ... def __get__(self, obj, type=None): ... print '__get__', (self, obj, type) ... return 'value' ... ... def __set__(self, obj, type=None): ... print '__set__', (self, obj, type) ... ... def __delete__(self, obj, type=None): ... print '__delete__', (self, obj, type) ... >>> # use it in a class Y ... class Y(object): ... x = Prop() ... >>> a = Y() >>> a.x # all accesses to a.x are intercepted __get__ (<__main__.Prop object at 0x00877BC8>, <__main__.Y object at 0x00878108>, <class '__main__.Y'>) 'value' >>> a.x = 42 __set__ (<__main__.Prop object at 0x00877BC8>, <__main__.Y object at 0x00878108>, 42) >>> Y.x # Prop intercepts reads of the class attribute __get__ (<__main__.Prop object at 0x00877BC8>, None, <class '__main__.Y'>) 'value' >>> Y.x = 1 # But not assignments >>> Y.x 1 >>> class mc(object.__class__): # to intercept Y.x assignment ... x = Prop() # I have to define this ... >>> class Y(object): ... __metaclass__ = mc ... >>> Y.x # now all accesses to Y.x are intercepted __get__ (<__main__.Prop object at 0x00876AB8>, <class '__main__.Y'>, <class '__main__.mc'>) 'value' >>> Y.x = 1 __set__ (<__main__.Prop object at 0x00876AB8>, <class '__main__.Y'>, 1) >>> a = Y() # But not accesses to a.x >>> a.x Traceback (most recent call last): File "<stdin>", line 1, in ? AttributeError: 'Y' object has no attribute 'x' >>> As you can see, the only way to intercept assignment to Y.x is to stick a property Y's class, i.e. the metaclass (or to modify __setattr__ in the metaclass, but it amounts to the same thing). In C++, a mutable static data member can be modified via the class Y::x = 1; or an instance of the class a.x = 1; I notice that Python supports this sort of dual access for reading attributes and calling static functions, but getting that behavior for mutable attributes seems unreasonably difficult: I need a property in the metaclass *and* in the class. 1. To throw out a straw-man suggestion, what about adding an additional protocol __set2__ which, if found, will be called instead of __set__ both for reading _and_ writing attributes on the class? 2. What are the optional type=None arguments for? It seems as though only the middle argument (obj) is ever None. I just copied this protocol out of descrintro.html 3. Is there documentation for __delete__ anywhere? -- Dave Abrahams Boost Consulting www.boost-consulting.com

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Needed: regexp maintainer
by Guido van Rossum 24 Feb '03

24 Feb '03

I notice with some despair that regular expression bugs and patches in SF don't get fixed. Assigning these to effbot seems a black hole. Is there someone who would like to take up maintenance of the SRE code? --Guido van Rossum (home page: http://www.python.org/~guido/)

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Weekly Python Bug/Patch Summary
by Skip Montanaro 23 Feb '03

23 Feb '03

Bug/Patch Summary ----------------- 358 open / 3367 total bugs (+22) 122 open / 1985 total patches (-3) New Bugs -------- unreliable file.read() error handling (2002-02-23) http://python.org/sf/521782 after using pdb readline does not work correctly (2003-01-28) http://python.org/sf/676342 classic division in demos/ directory (2003-02-16) http://python.org/sf/687648 Future division breaks mpz (2003-02-16) http://python.org/sf/687654 _iscommand() in webbrowser module (2003-02-16) http://python.org/sf/687747 Bundlebuilder needs to pre-convert resource files (2003-02-17) http://python.org/sf/688007 macresource should handle readonly applesingle files (2003-02-17) http://python.org/sf/688011 IDLE does not work on Mac OS X (2003-02-17) http://python.org/sf/688266 Applet support is broken (2003-02-18) http://python.org/sf/688907 64-bit int and long hash keys incompatible (2003-02-19) http://python.org/sf/689659 Docs page has no PEPs link (2003-02-19) http://python.org/sf/689826 Imports can deadlock (2003-02-20) http://python.org/sf/689895 2.3a2 build fails under IRIX 6.5 (2003-02-20) http://python.org/sf/690012 test_posix fails when run in non-interactive mode (2003-02-20) http://python.org/sf/690081 sys.last_type is missing (2003-02-20) http://python.org/sf/690109 robotparser only applies first applicable rule (2003-02-20) http://python.org/sf/690214 lines run together on input (2003-02-20) http://python.org/sf/690285 2.3a2 Sol8 make fails at _iconv_codec. (2003-02-20) http://python.org/sf/690309 2.3a2 build fails on Solaris: posixmodule (2003-02-20) http://python.org/sf/690317 test_tarfile fails on MacOS9 (2003-02-20) http://python.org/sf/690341 register command not listed in command line help (2003-02-20) http://python.org/sf/690389 can't build bsddb for 2.3a2 (2003-02-20) http://python.org/sf/690419 apply fails to check if warning raises exception (2003-02-20) http://python.org/sf/690435 test_cpickle overflows stack on MacOS9 (2003-02-21) http://python.org/sf/690622 re.LOCALE, umlaut and \w (2003-02-21) http://python.org/sf/690974 _POSIX_C_SOURCE redefined (2003-02-21) http://python.org/sf/691005 shutil.copytree documentation bug (2003-02-22) http://python.org/sf/691276 codecs.open(filename, 'U', 'UTF-16') corrupts text (2003-02-22) http://python.org/sf/691291 New Patches ----------- array.append is sloooow (2003-02-16) http://python.org/sf/687598 2.3 .spec file for building RPMs. (2003-02-18) http://python.org/sf/688584 Closed Bugs ----------- Long module names fail on the Mac (2001-09-05) http://python.org/sf/458874 standard include paths on command line (2002-07-31) http://python.org/sf/589427 Have PythonLauncher use #! line (2003-01-28) http://python.org/sf/676358 Whats new: Obligatory source code encodings if not ASCII (2003-02-09) http://python.org/sf/683416 bundlebuilder and spaces in filenames (2003-02-12) http://python.org/sf/685373 turtle circle() documentation error (2003-02-12) http://python.org/sf/685775 Closed Patches -------------- sys.path[0] should contain absolute pathname (2003-01-08) http://python.org/sf/664376 using gcc on cygwin for config (2003-02-05) http://python.org/sf/681504 Add download_url to setup() (2003-02-10) http://python.org/sf/683939 Fix for verbosity (2003-02-10) http://python.org/sf/684398 logging.handlers.SMTPHandler and single 'to' address (2003-02-13) http://python.org/sf/686379 add os.sep and friends to os.path (2003-02-13) http://python.org/sf/686397 Remove unncessary casts for PyEval_GetFrame() (2003-02-14) http://python.org/sf/686601

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call for Windows developers
by Thomas Heller 22 Feb '03

22 Feb '03

(This may be off-topic, but only slightly IMO.) I'm looking for one, two, or three experienced Python developers on Windows to participate in an exciting open-source project. As some people on this list might know, the ctypes project http://starship.python.net/crew/theller/ctypes.html has had a good start. In short, ctypes is an improved calldll replacement. The longer description is that it lets you in pure Python build, access, and manipulate simple, but also very complicated C data types (structures, unions, pointers, function pointers, callback functions) and use them to call functions in shared libraries/dlls. It currently runs on Windows, Linux, and MacOS X, the latter two with the help of the libffi library. Not only allows it to call, for example, win32 functions not (yet) exposed by Mark Hammond's win32all stuff, I think it is powerful enough to create bindings in pure Python to whole systems or frameworks. (That's the reason I think this post is not totally off-topic for this forum). Using ctypes is sometimes like programming C in a Python syntax, this may sound strange, but it's where I as a Python and C hacker feel quite at home ;-), just that I don't need the compiler any more... I would now like to create a COM framework. ctypes makes it easy to access COM vtables, and also easy to build them at runtime. Different from Mark's pythoncom, it would concentrate more on custom interfaces than on IDispatch - just what is needed if you have to interface to clients and servers implemented in ATL. My ultimate goal would be to be able to write ActiveX controls in pure Python, and write containers for AX controls in pure Python. So far, I have written proof-of-concept code with fairly good typelibrary/typeinfo support for both the client side and the server side. I have local and inproc servers running, can send and receive events via the connection point mechanism, can automatically create type libraries for COM interfaces written in Python, can decompile type libraries and generate Python source code wrappers for them, so that it's easy to use these interfaces in Python, and so on. All for simple cases only, though. As things usually go, I'm not happy with this code, although I've learned a lot, and started the first rewrite. The rewritten code is in the ctypes CVS repository, in a sandbox subdirectory. Supporting open-source projects is a large goal, and I'm quite sure I cannot do it for the ctypes COM stuff alone. So currently I have to decide whether this stays at the level of 'ctypes sample code', or if it will evolve into a useful addition to the Python toolkit on Windows, but, I need some help. Thanks for the attention, Thomas

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new format codes for getargs.c
by Thomas Heller 22 Feb '03

22 Feb '03

I've implemented a 'k' format code for getargs.c, and uploaded a patch for it http://www.python.org/sf/595026. This code accepts integers or longs, does no range checking, and returns the lower bits in an unsigned long. Is this also the fix for the hex constant issue which has been discussed here before? Are extension writers supposed to replace 'i' with 'k' in the PyArg_Parse calls in their extensions now? Then, I'm not sure how to proceed. Sure, a 'K' format code, which returns a LONG_LONG will also be needed, and I can implement that. Are the other changes proposed in the SF item (changes to the 'B', 'H', 'I' codes) needed? Do I have to add code somewhere to test these format codes or the Py.._From..Mask functions, probably in testcapi.c? Thomas

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2.3a2 problem: iconv module raising RuntimeError
by Neal Norwitz 22 Feb '03

22 Feb '03

There are already 2 bug reports with the build failing because the iconv module raises a RuntimeError. A patch to setup.py is below. The patch corrects the problem, but should anything else be done? The problem is that iconv builds ok, but the iconv_open fails so the module initialization failed, IIRC. Neal -- Index: setup.py =================================================================== RCS file: /cvsroot/python/python/dist/src/setup.py,v retrieving revision 1.146 diff -w -u -r1.146 setup.py --- setup.py 18 Feb 2003 10:24:34 -0000 1.146 +++ setup.py 20 Feb 2003 23:09:35 -0000 @@ -207,7 +207,7 @@ self.get_ext_filename(self.get_ext_fullname(ext.name))) try: imp.load_dynamic(ext.name, ext_filename) - except ImportError, why: + except (ImportError, RuntimeError), why: if 1: self.announce('*** WARNING: renaming "%s" since importing it'

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SCO Open Server 5.0.x thread support
by Pablo Endres 22 Feb '03

22 Feb '03

Hi, I've been trying for some time to build Python-2.2.x with thread support for SCO Open Server 5.0.5, with no luck. I'm using the FSU pthreads-3.9 library included in Skunkware. Any ideas on what should be done?? Is there thread support for this platform. Thanks in advance -- Democracy is two wolves and a sheep voting on what to have for dinner. Liberty is two wolves attempting to have a sheep for dinner and finding a well-informed, well-armed sheep. Pablo Endres Centro de Datos GSM: +584127347610

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Re: various unix platform build/test issues
by Chermside, Michael 22 Feb '03

22 Feb '03

Raymond Hettinger writes: > After Neal's changes to PyArg_ParseTuple, will Tim still > be able to use a floating argument to the wink() function > which has only been documented to accept a boolean state? Yes, but I want to know what happens when I try this: <1+0.5j wink> -- Michael Chermside

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Releasing Python 2.2.3 -- call for patches
by Guido van Rossum 21 Feb '03

21 Feb '03

I think it would be a good idea to release Python 2.2.3 soon -- say within a few weeks. I plan this to be a low-key release: all it does is add various important bugfixes, most of which were backported from 2.3. This is in tune with the Python-in-a-Tie idea for Python 2.2 (any idea what happened to the PBF plans for that?). If you have or know of something that you think should go into 2.2.3 but isn't in CVS yet, please let me know. The best way is to simply make the changes in CVS to the release22-maint branch. Do this only for things that are clearly bugfixes that introduce no backwards incompatibilities. When in doubt, use the second-best way. The second-best way is to (re)open a SF patch and assign it to me. --Guido van Rossum (home page: http://www.python.org/~guido/)

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