Mailman 3 November 2002 - Python-Dev

Metaclass insanity - another use case
by Phillip J. Eby Nov. 6, 2002

Nov. 6, 2002

I was reading the "metaclass insanity" thread this morning about dotted __name__ for nested classes, and I thought I should chime in that I've actually *used* this technique. That is, I've had classes of the form: class outer: class inner: ... And then regenerated 'inner' such that inner.__name__ == 'outer.inner' and stored it in globals()['outer.inner']. This *does* work with existing pickle code; in fact it worked as far back as Python 1.5.2! As for *why* I had inner … [View More]

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Possible ideas from Strongtalk (static typing for Smalltalk)?
by Hamish Lawson Nov. 5, 2002

Nov. 5, 2002

I recently came across an announcement about the the Strongtalk system, which contains the first fully developed strong, static type system for Smalltalk. I wondered whether there might be useful ideas there for those looking into static typing for Python. http://www.cs.ucsb.edu/projects/strongtalk/pages/index.html Hamish Lawson

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Re: [Python-Dev] [#527371] sre bug/patch
by Guido van Rossum Nov. 5, 2002

Nov. 5, 2002

> Just be sure to keep the code compatible with Python 1.5.1 (see PEP > 291). Oops, I meant Python 1.5.2. --Guido van Rossum (home page: http://www.python.org/~guido/)

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bz2module.c breaks regression tests
by Jeremy Hylton Nov. 5, 2002

Nov. 5, 2002

I just did a cvs update and a fresh build of Python dies with a segfault immediately after running test_bz2. build-pydebug> ./python ../Lib/test/regrtest.py test_bz2 test_grammar test_bz2 /usr/home/jeremy/src/python/dist/src/Lib/test/test_bz2.py:30: RuntimeWarning: mktemp is a potential security risk to your program self.filename = tempfile.mktemp("bz2") test_grammar Segmentation fault (core dumped) A partial gdb stack trace shows that it's dying in PyObject_Malloc(). I'm running with a … [View More]debug build of Python. Not sure what, if anything, it would do with a release build. #0 0x080828b7 in PyObject_Malloc (nbytes=17) at ../Objects/obmalloc.c:581 #1 0x08082f5c in _PyObject_DebugMalloc (nbytes=1) at ../Objects/obmalloc.c:992 #2 0x080553e5 in parsetok (tok=0x81b2fc0, g=0x81466a8, start=257, err_ret=0xbfffdfe0, flags=0) at ../Parser/parsetok.c:137 #3 0x08055218 in PyParser_ParseStringFlagsFilename ( s=0x401fcd44 "if 1:\n exec u'z=1+1\\n'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\'\\\\n'\n del z\n exec u'z=1+1'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\''\n", filename=0x0, g=0x81466a8, start=257, err_ret=0xbfffdfe0, flags=0) at ../Parser/parsetok.c:56 #4 0x08055156 in PyParser_ParseStringFlags ( s=0x401fcd44 "if 1:\n exec u'z=1+1\\n'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\'\\\\n'\n del z\n exec u'z=1+1'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\''\n", g=0x81466a8, start=257, err_ret=0xbfffdfe0, flags=0) at ../Parser/parsetok.c:31 #5 0x080e653f in PyParser_SimpleParseStringFlags ( str=0x401fcd44 "if 1:\n exec u'z=1+1\\n'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\'\\\\n'\n del z\n exec u'z=1+1'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\''\n", start=257, flags=0) at ../Python/pythonrun.c:1193 #6 0x080e6580 in PyParser_SimpleParseString ( str=0x401fcd44 "if 1:\n exec u'z=1+1\\n'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\'\\\\n'\n del z\n exec u'z=1+1'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\''\n", start=257) at ../Python/pythonrun.c:1203 #7 0x080e5fbc in PyRun_String ( str=0x401fcd44 "if 1:\n exec u'z=1+1\\n'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\'\\\\n'\n del z\n exec u'z=1+1'\n if z != 2: raise TestFailed, 'exec u\\'z=1+1\\''\n", start=257, globals=0x4020c994, locals=0x4020c3f4) at ../Python/pythonrun.c:1025 #8 0x080c431e in exec_statement (f=0x818410c, prog=0x401fcd28, globals=0x4020c994, locals=0x4020c3f4) at ../Python/ceval.c:3786 #9 0x080bca30 in eval_frame (f=0x818410c) at ../Python/ceval.c:1539 #10 0x080c0b69 in PyEval_EvalCodeEx (co=0x40263b28, globals=0x4020c994, locals=0x0, args=0x815907c, argcount=0, kws=0x815907c, kwcount=0, defs=0x0, defcount=0, closure=0x0) at ../Python/ceval.c:2542 #11 0x080c2996 in fast_function (func=0x402222b4, pp_stack=0xbfffe328, n=0, na=0, nk=0) at ../Python/ceval.c:3282 #12 0x080c2818 in call_function (pp_stack=0xbfffe328, oparg=0) at ../Python/ceval.c:3251 #13 0x080beb80 in eval_frame (f=0x8158f24) at ../Python/ceval.c:1997 #14 0x080c0b69 in PyEval_EvalCodeEx (co=0x4021e238, globals=0x4020c994, locals=0x4020c994, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0, defcount=0, closure=0x0) at ../Python/ceval.c:2542 #15 0x080b6abc in PyEval_EvalCode (co=0x4021e238, globals=0x4020c994, locals=0x4020c994) at ../Python/ceval.c:478 #16 0x080dadc3 in PyImport_ExecCodeModuleEx ( name=0xbfffed48 "test.test_grammar", co=0x4021e238, pathname=0xbfffe440 "/usr/home/jeremy/src/python/dist/src/Lib/test/test_grammar.pyc") at ../Python/import.c:530 Jeremy [View Less]

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Re: List slice assignment and custom sequences
by Michael Hudson Nov. 5, 2002

Nov. 5, 2002

On Tue, 5 Nov 2002, Ronald Oussoren wrote: > > On Tuesday, Nov 5, 2002, at 15:03 Europe/Amsterdam, Michael Hudson > wrote: > > > Ronald Oussoren <oussoren(a)cistron.nl> writes: > > > >> No, I want to replace part of a sequence by another sequence. I don't > >> understand _why_ the RHS must be a list if the LHS is one. > > > > Because Objects/listobject.c:list_ass_slice pokes directly into the > > object passed on the RHS. … [View More]

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Re: [Python-Dev] metaclass insanity
by Guido van Rossum Nov. 5, 2002

Nov. 5, 2002

> Keeping a definition of some X (whether X is a class, a function, > whatever) as local as feasible has one obvious merit which I have > already pointed out: a reader of the code need NOT ask himself > "where is this X defined" when X is used, nor "how is this X used" > when X is defined -- the answers become immediately obvious by the > very way the code is structure... X is defined right here and used > right here. Yes. However this is counterbalanced by the … [View More]

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Re: [Python-Dev] metaclass insanity
by Christopher Armstrong Nov. 5, 2002

Nov. 5, 2002

Guido van Russom wrote on Mon, 04 Nov 2002 15:54:48 -0500 > Can someone provide a reason why you'd want to use nested classes? > I've never felt this need myself. What are the motivations? Yes. In Reality (a Twisted Matrix Labs project), a text-based virtual world simulation framework, we have a system that can automatically generate Interface definitions from classes (with a metaclass that builds them at class-def time). Twisted has an Interface/adapter/ componentized system similar to … [View More]

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Re: [Python-Dev] metaclass insanity
by Michael Hudson Nov. 5, 2002

Nov. 5, 2002

Just van Rossum <just(a)letterror.com> writes: > While I'm sure this was just a theoretical example, _this_ specific > case is much easier written as a generator (and I _love_ the idiom > of making the __iter__ method a generator, I think it's > underused...). Maybe it's underused because it hasn't occured to people? It certainly does look neat. Cheers, M. now struggling to think of an iterator that's better done as a class than a generator... -- incidentally, asking … [View More]

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Re: [Python-Dev] Becoming a python contributor
by Michael Hudson Nov. 5, 2002

Nov. 5, 2002

martin(a)v.loewis.de (Martin v. Loewis) writes: > Unfortunately, adding a Status field is not possible on SF. Which reminds me: how much longer are we going to have to put up with SF for bugs? Is the roundup work getting anywhere? Cheers, M. -- > So what does "abc" / "ab" equal? cheese -- Steve Holden defends obscure semantics on comp.lang.python

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[#454030] distutils cannot link C++ code with GCC
by Gustavo Niemeyer Nov. 5, 2002

Nov. 5, 2002

Can someone please review the proposed solution attached on bug #454030, fixing the following bugs: [#413582] g++ must be called for c++ extensions [#454030] distutils cannot link C++ code with GCC Thank you! -- Gustavo Niemeyer [ 2AAC 7928 0FBF 0299 5EB5 60E2 2253 B29A 6664 3A0C ]

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