Issue 28974: Make default format be equivalent to str (original) (raw)

Issue28974

Created on 2016-12-14 21:52 by serhiy.storchaka, last changed 2022-04-11 14:58 by admin. This issue is now closed.

Messages (4)
msg283220 - (view)	Author: Serhiy Storchaka (serhiy.storchaka) *	Date: 2016-12-14 21:52
Originally PEP 3101 defined the default __format__ implementation, object.__format__ as def __format__(self, format_spec): return format(str(self), format_spec) After few changes (, ) it now looks as def __format__(self, format_spec): assert format_spec == '' return format(str(self), '') Proposed patch makes it yet simpler: def __format__(self, format_spec): assert format_spec == '' return str(self) This is equivalent to the previous form except obscure case when str() returns not exact str, but strict subclass with overridden __format__. The benefit of this change is simpler semantical model of the default implementation. See the start of the discussion in and the discussion on Python-Dev: https://mail.python.org/pipermail/python-dev/2016-October/146765.html.
msg293605 - (view)	Author: Serhiy Storchaka (serhiy.storchaka) *	Date: 2017-05-13 08:36
What are your thoughts about this Eric?
msg293607 - (view)	Author: Eric V. Smith (eric.smith) *	Date: 2017-05-13 09:08
I'm okay with this change.
msg293609 - (view)	Author: Serhiy Storchaka (serhiy.storchaka) *	Date: 2017-05-13 09:40
New changeset 7e19dbc92ec06a987eaae72f7cdfd32006aa4960 by Serhiy Storchaka in branch 'master': bpo-28974: `object.__format__(x, '')` is now equivalent to `str(x)` (#506) https://github.com/python/cpython/commit/7e19dbc92ec06a987eaae72f7cdfd32006aa4960