Mailman 3 April 2001 - Python-Dev

Late enhancements breaks termios build
by Mark Favas April 5, 2001

April 5, 2001

In the past day or so, extra functionaility has been added to the CVS version of the termios module. This breaks the compilation of termios.c on Tru64 Unix, as a number of the new constants collide with macros of the same name defined in /usr/include/sys/ioctl.h - so the #ifdef NEW_THING succeeds, but with incompatible values from ioctl.h, rather than compatible values from termios.h. I thought we were at the "fix bugs" stage, rather than the "it'd be nice to add this" <wink>. Yes, I'll … [View More]

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Little hits add up...
by Mark Favas April 5, 2001

April 5, 2001

Since it's a quiet time on python-dev at the moment <grin>, I thought I'd just toss this bedraggled parrot in... Every now and then, the comment arises "this <enhancement X> should only incur a small performance hit". I just ran one of my apps under 1.5.2+ and 2.1b2. The little hits along the way have here added up to a 26% slowdown. Around the time 2.0 was released, there was a brief thread along the lines of "let's get 2.0 out the door, and tune it up in 2.1 - there's some low-… [View More]

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Case-sensitive import
by Tim Peters April 4, 2001

April 4, 2001

I'm still trying to sort this out. Some concerns and questions: I don't like the new MatchFilename, because it triggers on *all* platforms that #define HAVE_DIRENT_H. Anyone, doesn't that trigger on straight Linux systems too (all I know is that it's part of the Single UNIX Specification)? I don't like it because it implements a woefully inefficient algorithm: it cycles through the entire directory looking for a case-sensitive match. But there can be hundreds of .py files in a directory, … [View More]

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s1 == (sf % (s1 / sf))? A bad idea?
by pf＠artcom-gmbh.de April 4, 2001

April 4, 2001

At the moment it is very silent on Python-dev. I guess you guys are all out hunting dead parrots, which escaped from the cages on April 1st. ;-) So this might be the right moment to present a possibly bad idea (TM). see below. Regards, Peter -- Peter Funk, Oldenburger Str.86, D-27777 Ganderkesee, Germany, Fax:+49 4222950260 office: +49 421 20419-0 (ArtCom GmbH, Grazer Str.8, D-28359 Bremen, Germany) PEP: XXXX Title: String Scanning Version: $Revision$ Author: pf(a)artcom-gmbh.de (Peter Funk)… [View More] Status: Not yet Draft Type: Standards Track Python-Version: 2.2 Created: 02-Apr-2001 Post-History: Abstract This document proposes a string scanning feature for Python to allow easier string parsing. The suggested syntax change is to allow the use of the division '/' operator for string operands as counterpart to the already existing '%' string interpolation operator. In current Python this raises an exception: 'TypeError: bad operand type(s) for /'. With the proposed enhancement the expression string1 / format2 should either return a simple value, a tuple of values or a dictionary depending on the content of the right operand (aka. format) string. Copyright This document is in the public domain. Specification The feature should mimic the behaviour of the scanf function well known to C programmers. For any format string sf and any matching input string si the following pseudo condition should be true: string.split( sf % (si / sf) ) == string.split( si ) That is modulo any differences in white space the result of the string interpolation using the intermediate result from the string scanning operation should look similar to original input string. All conversions are introduced by the % (percent sign) character. The format string may also contain other characters. White space (such as blanks, tabs, or newlines) in the format string match any amount of white space, including none, in the input. Everything else matches only itself. Scanning stops when an input character does not match such a format character. Scanning also stops when an input conversion cannot be made (see below). Examples Here is an example of an interactive session exhibiting the expected behaviour of this feature. >>> "12345 John Doe" / "%5d %8s" (12345, 'John Doe') >>> "12 34 56 7.890" / "%d %d %d %f" (12, 34, 56, 7.8899999999999997) >>> "12345 John Doe, Foo Bar" / "%(num)d %(n)s, %(f)s %(b)s" {'n': 'John Doe', 'f': 'Foo', 'b': 'Bar', 'num': 12345} >>> "1 2" / "%d %d %d" Traceback (innermost last): File "<stdin>", line 1, in ? TypeError: not all arguments filled Discussion This should fix the assymetry between arithmetic types and strings. It should also make the life easier for C programmers migrating to Python (see FAQ 4.33). Those poor souls are acustomed to scanf as the counterpart of printf and usually feel uneasy to convert to string slitting, slicing or the syntax of regular expressions. Security Issues There should be no security issues. Implementation There is no implementation yet. This is just an idea. Local Variables: mode: indented-text indent-tabs-mode: nil End: [View Less]

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Re: s1 == (sf % (s1 / sf))? A bad idea?
by Paul F. Dubois April 3, 2001

April 3, 2001

Well, as usual I have a complete lack of aesthetic judgment because *I* thought it was a great idea. I could just picture my scientists parsing input lines from data files with it. A similar feature in Basis is heavily used. Then again, I *love* s % f. See, I'm totally sick.

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Python9 footage on www.technetcast.com
by Guido van Rossum April 3, 2001

April 3, 2001

Dr. Dobb's technetcast is playing audio and video footage from Python9: video of a brief interview with me, and (coming up next?) audio from the two keynotes (Bruce Eckel's and mine). Go to www.technetcast.com (RealAudio support required, I believe.) --Guido van Rossum (home page: http://www.python.org/~guido/)

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Making types behave like classes
by Paul Prescod April 2, 2001

April 2, 2001

These are some half-baked ideas about getting classes and types to look more similar. I would like to know whether they are workable or not and so I present them to the people best equipped to tell me. Many extension types have a __getattr__ that looks like this: static PyObject * Xxo_getattr(XxoObject *self, char *name) { // try to do some work with known attribute names, else: return Py_FindMethod(Xxo_methods, (PyObject *)self, name); } Py_FindMethod can (despite its name) return any … [View More]

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RE: [Python-Dev] PEP: Use site-packages on all platforms
by Moore, Paul April 2, 2001

April 2, 2001

From: Guido van Rossum [mailto:guido@digicool.com] > > I think this is a good idea. Submit the PEP to Barry! Done. > I doubt that we can introduce this into Python 2.1 this late in the > release cycle. Would that be a problem? I thought as much. I can't see it being a major issue. My only concern (as noted in the PEP) is that with distutils becoming more commonly used, there will be more and more packages installed using distutils, and so ending up in the directory which … [View More]

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Perl and Python to begin joint development
by Jeremy Hylton April 2, 2001

April 2, 2001

[FYI: This press release was also sent to c.l.py.a. Dan and I expect to have the release schedule PEP ready soon. And, yes, that's Parrot Enhancement Proposal (PEP). --jeremy] 04/01/2001 SEBASTOPOL, CA Perl and Python to begin joint development Larry Wall, the creator of Perl, and Guido van Rossum, creator of Python, today announced that their respective projects are about to begin a period of joint development. According to the language designers, the idea surfaced at last year's Open … [View More]Source Convention - "We at the Perl Conference were aware of a need for a new direction for Perl and for its community, and that's why we announced the work on Perl 6," said an excited Wall. "At the same time, Guido was thinking very hard about Python 2.0 and where it was going, and we got together and started talking about helping each other out." Initially, the pair planned to have their development communities working together for mutual benefit. van Rossum cited some of the technical reasons for the collaboration: "Perl's highly powerful regular expression engine would be integrated into Python, and would benefit us greatly; in return, we've got a number of things right that Perl could gain from, such as signal handling and robust software engineering." However, as both designers talked about the changes their languages were going through, they came to the conclusion that they had much to share at the language level as well as the interpreter level. According to Larry Wall, "Perl's always been about taking the best features of all the other languages available; it's perfectly natural for us to integrate the best features of Python too." The specifications for the combined language, called Parrot, will be documented in the forthcoming book "Programming Parrot In A Nutshell", to be published by O'Reilly and Associates. In the meantime, the Python Software Foundation is said to be making arrangements to merge with Yet Another Society. YAS president Kevin Lenzo was delighted at the move: "It's a natural extension of what YAS was set up to facilitate - collaboration and communication between programming communities." Parrot development will begin with the merger of the Py3K development team with the Perl 6 internals working group; Jeremy Hylton and Dan Sugalski will be the joint development leads. Larry Wall and Guido van Rossum both accepted positions at the Vancouver, Canada development company ActiveState. A spokesman for ActiveState said that the company was obviously very pleased with the decision, but denied that ActiveState had influenced it in any way. [View Less]

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nano-threads?
by Neil Schemenauer April 1, 2001

April 1, 2001

Here are some silly bits of code implementing single frame coroutines and threads using my frame suspend/resume patch. The coroutine example does not allow a value to be passed but that would be simple to add. An updated version of the (very experimental) patch is here: http://arctrix.com/nas/generator3.diff For me, thinking in terms of frames is quite natural and I didn't have any trouble writing these examples. I'm hoping they will be useful to other people who are trying to get their … [View More]

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