| msg27376 - (view) |
Author: Bernhard Herzog (bernhard) |
Date: 2006-01-29 01:04 |
| The builtin float and the function string.atof have become locale aware in Python 2.4: Python 2.4.2 (#1, Nov 29 2005, 16:07:55) [GCC 2.95.4 20011002 (Debian prerelease)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import locale >>> import string >>> locale.setlocale(locale.LC_ALL, "de_DE") 'de_DE' >>> float("1,5") 1.5 >>> string.atof("1,5") 1.5 This doesn't match what's specified in pep 331: - float() and str() stay locale-unaware. It also doesn't match the documentation for atof: Convert a string to a floating point number. The string must have the standard syntax for a floating point literal in Python, optionally preceded by a sign ("+" or "-"). Note that this behaves identical to the built-in function float() when passed a string. The documentation for float() doesn't state which format is accepted by float(), though. The reason for this behavior is ultimately, that PyOS_ascii_strtod accepts the locale specific convention in addition to the "C"-locale/python convention, even though the comment in the code preceding its definition states: This function behaves like the standard strtod() function does in the C locale. |
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| msg27377 - (view) |
Author: Georg Brandl (georg.brandl) *  |
Date: 2006-02-17 12:19 |
| Logged In: YES user_id=1188172 Martin, you checked in the patch which is mentioned in PEP 331. Is this correct behavior? |
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| msg27378 - (view) |
Author: Martin v. Löwis (loewis) * |
Date: 2006-05-04 04:42 |
| Logged In: YES user_id=21627 It's a bug. As bernhard says, it originates from PyOS_ascii_strtod accepting both forms, which in turn happens because it just leaves the locale-specific decimal point in the string, only replacing the . with the locale-specific point. Then, the platform's strtod will happily accept the locale-specific version. I'd like Gustavo Carneiro to comment. |
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| msg27379 - (view) |
Author: Gustavo J. A. M. Carneiro (gustavo) * |
Date: 2006-05-04 09:47 |
| Logged In: YES user_id=908 My comment is, is "PyOS_ascii_strtod accepting both forms" something that is harmful and should be fixed? I didn't exactly write the PyOS_ascii_strtod code; I only integrated it with Python. But if we really need to fix this, I'll try to figure out how to make it not accept floating points in locale aware format; if necessary I'll ask help from the original author of the code, Alexander Larsson. |
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| msg27380 - (view) |
Author: Georg Brandl (georg.brandl) * |
Date: 2006-05-08 18:00 |
| Logged In: YES user_id=849994 I grepped around and found PyOS_ascii_strtod in the following places: * stropmodule::atof * cPickle::load_float (the writing of locale dependent floats was fixed recently) * floatobject::PyFloat_FromString * complexobject::complex_subtype_from_string In my opinion, all these should not tolerate localized floats, so Gustavo, please ask the original author how to achieve this. |
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| msg27381 - (view) |
Author: Martin v. Löwis (loewis) * |
Date: 2006-05-12 14:14 |
| Logged In: YES user_id=21627 Unassigning myself - I don't plan to work on this anytime soon. |
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| msg27382 - (view) |
Author: Gustavo J. A. M. Carneiro (gustavo) * |
Date: 2006-05-13 11:59 |
| Logged In: YES user_id=908 I'm quite busy at this moment, but I'll send a patch soon, promise. |
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| msg27383 - (view) |
Author: Gustavo J. A. M. Carneiro (gustavo) * |
Date: 2006-05-16 16:35 |
| Logged In: YES user_id=908 It seems I can't upload files?! I have put the patch to fix this problem, including unit test, here: http://www.gnome.org/~gjc/python-1417699.diff |
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| msg27384 - (view) |
Author: Bernhard Herzog (bernhard) |
Date: 2006-06-10 19:18 |
| Logged In: YES user_id=2369 gustavo, your patch seems to work fine. However, it leads to some test failures because the testsuite already tests for the wrong behaviour. I've uploaded a version of your patch that in addtion to your changes contains modifications to the test suite so that it tests for the new behavior and also tests some more variations of floating point literals accepted by float(). It would be nice if this patch could go into 2.5 before beta1 |
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| msg27385 - (view) |
Author: Martin v. Löwis (loewis) * |
Date: 2006-07-03 12:21 |
| Logged In: YES user_id=21627 Thanks for the report and the patch. Committed as r47212. I don't think it should get backported to 2.4, as it may break existing code. |
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