Issue 13280: argparse should use the new Formatter class (original) (raw)

Issue13280

Created on 2011-10-27 20:19 by poke, last changed 2022-04-11 14:57 by admin. This issue is now closed.

Messages (4)
msg146516 - (view)	Author: Patrick Westerhoff (poke)	Date: 2011-10-27 20:19
Hey, according to PEP 3101, the new string.Formatter class is supposed to replace the old string formatting with %. At least that is what I was always thinking. Given that argparse is a Python 3.2+ exclusive module, I think it should make use of that new formatting method. Is there any special reason why that is not the case and the old %-formatting is used? It feels a bit weird to have Python 3 code using only string.Formatter and then have a short section where the old formatter is used – especially when that module was introduced with Python 3.2.
msg146520 - (view)	Author: Florent Xicluna (flox) *	Date: 2011-10-27 21:42
Well argparse exists since 2006 (ref [1]), and "should work on Python >= 2.3" (ref [2]). It was merged in the standard library with Python 3.2. However, I agree we may switch to the advanced string formatting for this module. [1] http://objectmix.com/python/180879-%5Bann%5D-argparse-module.html [2] http://pypi.python.org/pypi/argparse#compatibility
msg146533 - (view)	Author: Raymond Hettinger (rhettinger) *	Date: 2011-10-28 03:14
There's no reason to switch the implementation. The % formatting isn't going away and we've decided against doing switch-overs in existing code (it risks introducing bugs while conferring zero benefits to users).
msg326708 - (view)	Author: paul j3 (paul.j3) *	Date: 2018-09-30 06:50
Thinking about https://bugs.python.org/issue34744, I realized that the new style formatting could provide some added flexibility to the help lines. I think new style formatting could be added in parallel with the existing style, as an alternative, not as a replacement. With that option a help line like: 'help for {dest} or {option_strings[0]} default is {default}' could be used.