Mailman 3 January 2001 - Python-Dev

inspect.py
by Ka-Ping Yee Jan. 8, 2001

Jan. 8, 2001

Uh... hi. <sheepish look> I know i've all but dropped out of existence for a long time, what with my simultaneous first stints as a grad student, a teaching assistant, and a house cook (!) and all, but i didn't want to let this work go to waste. Now that the holidays are here i can *finally* try to get some work done! So, i've updated inspect.py in response to Barry's comments, and below is my reply to this old thread. I also wrote some regression tests. I tried to submit inspect.py … [View More]to SourceForge, but i got: ERROR Patch Uploaded ERROR - Submission failed PQsendQuery() -- query is too long. Maximum length is 16382 Does anyone know what's going on with that? Anyway, the latest module and regression tests are available at: http://www.lfw.org/python/inspect.py http://www.lfw.org/python/test_inspect.py for your perusal. On Thu, 26 Oct 2000 barry(a)wooz.org wrote: > Some thoughts after an initial scan of inspect.py: > > - The doc strings for the is*() functions aren't accurate. > E.g. ismodule() says that it asks whether "the object is a module > with the __file__ special attribute", but that isn't really what it > tests! Guido points out that builtin modules don't currently have > __file__ and besides, you're really testing that the type of the > object is ModuleType. Perhaps a different wording would be better, but i should at least clarify the intention: i wrote them that way because it seemed that the current objects export an unofficial "interface" by means of the special attributes they provide. The purpose of the "is*()" functions is to determine whether an object meets one of these interfaces. A complete interface would provide (1) a type-checker, (2) a constructor, and (3) the methods. As for (2), we don't normally allow construction of these things (except for wizards using the newmodule). As for (3), i suppose that one could further encapsulate these interfaces by providing spelled-out methods like "def getcode(f): return f.func_code", but it didn't seem worth the trouble. So that left just (1), and i had the other parts in mind while trying to describe (1). The type-checkers aren't of much use unless they accurately reflect the availability of the special attributes. Do you see what i'm trying to do? Maybe you can suggest a better way of doing it... anyway, i've tried to compromise in the docstrings as submitted. > - Don't make the predicate in getmembers() default to "lambda x: 1" > Instead make the default None, and skip the predicate test if it is > None. Okay, fine. > - getdoc()'s docstring should describe the margin munging it does. Okay, done. > - findsource() seems off-by one, e.g. > > >>> x = inspect.findsource(inspect.findsource) > >>> x[1] > 138 > > but the function really stars on line 139. 138 was the intended result here. Indeed the function starts on line 139 if you start counting from 1. The reason it returns 138 is that it's the index you would use for the array of lines (thus x[0][x[1]] or file.readlines()[138] is the first line of the function). Which way makes more sense? Should it be changed? > - I notice that currentframe() still uses the try/except trick to get > the frame object. It's much more efficient to provide a C > trampoline for getting that information. Sure, if there's a faster way, that's fine. It just wasn't something i expected to be used really often, and i wanted to write the module in pure Python so it could be easily maintained. I added a line to clobber the pure-Python currentframe() with sys._getframe() if it exists. > - If this were included in the library, we might want to 2.0-ify it. It currently doesn't rely on any 2.0 features, and it would be kind of nice to have it still work with 1.5 (especially if it is part of a drop-in documentation tool, as it is now, since it goes with htmldoc). -- ?!ng "Computers are useless. They can only give you answers." -- Pablo Picasso [View Less]

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Extending startup code: PEP needed?
by Martin v. Loewis Jan. 8, 2001

Jan. 8, 2001

Authors of extension packages often find the need to auto-import some of their modules. This is often needed for registration, e.g. a codec author (like Tamito KAJIYAMA, who wrote the JapaneseCodecs package) may need to register a search function with codecs.register. This is currently only possible by writing into sitecustomize.py, which must be done by the system administrator manually. To enhance the service of site.py, I've written the patch http://sourceforge.net/patch/?func=detailpatch&… [View More]

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Std tests failing, Windows: test_builtin test_charmapcodec test_pow
by Tim Peters Jan. 8, 2001

Jan. 8, 2001

I'm pretty sure the test_pow and test_charmapcodec failures aren't my doing. test_builtin fails because raw_input() isn't stripping a trailing newline. I've got my own code in this area that *may* be to blame, but I don't see how it could be. I note that fileobject.c's new function get_line_raw has the comment /* Internal routine to get a line for raw_input(): strip trailing '\n', raise EOFError if EOF reached immediately */ but the code doesn't look for a trailing newline (let alone strip one).

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Re: [Python-checkins] CVS: python/dist/src/Objects fileobject.c,2.96,2.97
by Greg Stein Jan. 7, 2001

Jan. 7, 2001

On Fri, Jan 05, 2001 at 06:43:07AM -0800, Guido van Rossum wrote: > Update of /cvsroot/python/python/dist/src/Objects > In directory usw-pr-cvs1:/tmp/cvs-serv3183 > > Modified Files: > fileobject.c > Log Message: > Restructured get_line() for clarity and speed. > > - The raw_input() functionality is moved to a separate function. > > - Drop GNU getline() in favor of getc_unlocked(), which exists on more > platforms (and is even a tad faster on my system)… [View More]

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readline module seems crippled - am I missing something?
by Skip Montanaro Jan. 6, 2001

Jan. 6, 2001

For a more-or-less throwaway script I'm working on I need a little input function similar to Emacs's read-from-minibuffer, which accepts both a prompt and an initial string for the input buffer. Seems like I ought to be able to whip something up using readline, but it's not happening. GNU readline's docs aren't the greatest, but I thought this simple script would work: import readline readline.insert_text("default") x = raw_input("?") print x I expected to see an editable "… [View More]

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function attributes as "true" class attributes & reclamation error
by Skip Montanaro Jan. 6, 2001

Jan. 6, 2001

You know, I thought of something (which was probably already obvious to the rest of you) while perusing Barry's patch. Attaching function attributes to unbound methods could really function like C++ static data members. You'd have to write accessor functions to make setting the attributes look clean, but that wouldn't be all bad. Precisely because you couldn't modify them through the bound method, there's be no chance you could make the mistake of modifying them that way and having them … [View More]

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PEP 208 comment
by Martin v. Loewis Jan. 6, 2001

Jan. 6, 2001

I just studied PEP 208 for the first time. Overall, it seems all natural and nice, but there is one one aspect I'd like to see changed: the naming of the type flag. Currently, it is called Py_TPFLAGS_NEWSTYLENUMBER. IMHO, nothing in a program should be called "new". The flag will still be there five years from now, but it won't be new anymore. Also, while the flag indicates that style of the numbers is new, it does not say what it does. So I propose to rename it; if nobody finds a better name, … [View More]

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Re: [Patches] [Patch #103123] PEP 232 implementation (function attributes)
by Skip Montanaro Jan. 6, 2001

Jan. 6, 2001

Oooo... I tried went to check out Barry's function attribute patch at http://sourceforge.net/patch/?func=detailpatch&patch_id=103123&group_id=5470 and got Fatal error: Call to a member function on a non-object in /usr/local/htdocs/alexandria/www/patch/index.php on line 55 in response. Any idea whazzup? Skip

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PEP 232 update and patch
by barry＠digicool.com Jan. 6, 2001

Jan. 6, 2001

I've updated PEP 232, function attributes, and uploaded a patch to SF. I couldn't coax cvs diff into including the new files Lib/test/test_funcattrs.py and Lib/test/output/test_funcattrs so I'll attach them below. PEP 232: http://python.sourceforge.net/peps/pep-0232.html SF patch #103123: http://sourceforge.net/patch/?func=detailpatch&patch_id=103123&group_id=5470 Enjoy, -Barry from test_support import verbose, TestFailed class F: def a(self): pass def b(): … [View More]

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RE: [Python-Dev] Add __exports__ to modules
by Bill Tutt Jan. 5, 2001

Jan. 5, 2001

I think I'm with Moshe on this one, whats wrong with just using underscores (__) to play the hiding game. Here's my silly language suggestion for this week: with self: .bar = foo bar.blah = .fubar .bar = .bar + 1 # etc.... Bill

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