Mailman 3 June 2005 - Python-Dev

misplaced PEP
by Nick Jacobson June 19, 2005

June 19, 2005

At the www.python.org/peps page, PEP 281 is erroneously listed in the "Finished PEPs (done, implemented in CVS)" section. ____________________________________________________ Yahoo! Sports Rekindle the Rivalries. Sign up for Fantasy Football http://football.fantasysports.yahoo.com

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gcmodule issue w/adding __del__ to generator objects
by Phillip J. Eby June 19, 2005

June 19, 2005

Working on the PEP 342/343 generator enhancements, I've got working send/throw/close() methods, but am not sure how to deal with getting __del__ to invoke close(). Naturally, I can add a "__del__" entry to its methods list easily enough, but the 'has_finalizer()' function in gcmodule.c only checks for a __del__ attribute on instance objects, and for tp_del on heap types. It looks to me like the correct fix would be to check for tp_del always, not just on heap types. However, when I tried this, I started getting warnings from the tests, saying that 22 uncollectable objects were being created (all generators, in test_generators). It seems that the tests create cycles via globals(), since they define a bunch of generator functions and then call them, saving the generator iterators (or objects that reference them) in global variables after investigating this a bit, it seems to me that either has_finalizer() needs to

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Propose to reject PEP 276 -- Simple iterator for ints
by Raymond Hettinger June 19, 2005

June 19, 2005

The principal use case was largely met by enumerate(). From PEP 276's rationale section: """ A common programming idiom is to take a collection of objects and apply some operation to each item in the collection in some established sequential order. Python provides the "for in" looping control structure for handling this common idiom. Cases arise, however, where it is necessary (or more convenient) to access each item in an "indexed" collection by iterating through each index and accessing each item in the collection using the corresponding index. """ Also, while some nice examples are provided, the proposed syntax allows and encourages some horrid examples as well: >>> for i in 3: print i 0 1 2 The backwards compatability section lists another problematic consequence; the following would stop being a syntax error and would become valid: x, = 1 The proposal adds iterability to all integers but silently does nothing for negative values. A minor additional concern is that floats are not given an equivalent capability (for obvious reasons) but this breaks symmetry with range/xrange which still accept float args. Raymond

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Propose to reject PEP 294 -- Type Names in the types Module
by Raymond Hettinger June 19, 2005

June 19, 2005

Introducing a new set of duplicate type names and deprecating old ones causes a certain amount of disruption. Given the age of the types module, the disruption is likely to be greater than any potential benefit that could be realized. Plenty of people will have to incur the transition costs, but no one will likely find the benefit to be perceptible. Suggest rejecting this PEP and making a note for Py3.0 to either sync-up the type names or abandon the types module entirely. Raymond

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Problem with embedded python
by Luisa June 19, 2005

June 19, 2005

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Propose to close PEP 254 -- Making Classes Look More Like Types
by Raymond Hettinger June 19, 2005

June 19, 2005

This PEP is an empty stub that is unlikely to ever get filled-out in a way that adds anything beyond what is already implemented and documented. Raymond

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Question about PEP 330 -- Python Bytecode Verification
by Raymond Hettinger June 19, 2005

June 19, 2005

Do we have *any* known use cases where we would actually run bytecode that was suspicious enough to warrant running a well-formedness check? In assessing security risks, the PEP notes, "Practically, it would be difficult for a malicious user to 'inject' invalid bytecode into a PVM for the purposes of exploitation, but not impossible." Can that ever occur without there being a far greater risk of malicious, but well-formed bytecode? If you download a file, foo.pyc, from an untrusted source and run it in a susceptible environment, does its well-formedness give you *any* feeling of security. I think not. There isn't anything wrong with having a verifier module, but I can't think of any benefit that would warrant changing the bytecode semantics just to facilitate one of the static stack checks. Raymond

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PEP for RFE 46738 (first draft)
by Simon Wittber June 19, 2005

June 19, 2005

Hello Chaps, The attached PEP (pep.txt) is for RFE 46738, which you can view here: http://sourceforge.net/tracker/index.php?func=detail&aid=467384&group_id=54… It provides a safe, documented class for serialization of simple python types. A sample implementation is also attached (gherkin.py). Critcism and comments on the PEP and the implementation are appreciated. Simon Wittber.

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Propose to reject PEP 313 -- Adding Roman Numeral Literals to Python
by Raymond Hettinger June 18, 2005

June 18, 2005

While the majority of Python users deem this to be a nice-to-have feature, the community has been unable to reach a consensus on the proper syntax after more than two years of intensive debate (the PEP was introduced in early April 2003). Most agree that there should be only-one-way-to-do-it; however, the proponents are evenly split into two camps, with the modernists preferring IX for nine and the classicists preferring VIIII which was the most likely spelling in ancient Rome. The classicists not only rely on set-in-stone tradition, they point to pragmatic issues such as avoidance of subtraction, ease of coding, easier mental parsing (much less error prone), and ease of teaching to beginners. They assert that the modernists have introduced unnecessary algorithmic complexity just to save two keystrokes. The modernists point to compatible Java implementations and current grade school textbooks. They believe that users from other languages will expect the IX form. Note however, not all the modernists agree on whether MXM would be a well-formed spelling of 1990; most, but not all prefer MCMXC despite its likelihood of being mis-parsed on a first reading. There is also a small but vocal user group demanding that lowercase forms be allowed. Their use cases fall into four categories: (i) academia, (ii) the legal profession, (iii) research paper writing, and (iv) powerpoint slideshows. Reportedly, this is also a common convention among Perl programmers. Links: http://hrsbstaff.ednet.ns.ca/waymac/History%20A/A%20Term%201/1.%20Rome/R oman_Numerals.htm http://www.sizes.com/numbers/roman_numerals.htm Raymond

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PyPI: no space left on device
by Gustavo Niemeyer June 18, 2005

June 18, 2005

PyPI seems to be out of space: % ./setup.py register --show-response running register Using PyPI login from /home/niemeyer/.pypirc --------------------------------------------------------------------------- Error... There's been a problem with your request psycopg.ProgrammingError: ERROR: could not extend relation "releases": No space left on device HINT: Check free disk space. -- Gustavo Niemeyer http://niemeyer.net

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