Mercurial > hg
view mercurial/thirdparty/attr/converters.py @ 34397:765eb17a7eb8
thirdparty: vendor attrs
The attrs package allows defining namedtuple-like classes with no weird
behavior and no runtime performance cost.
This patch vendors in attrs 17.2.0.
# no-check-commit
Differential Revision: https://phab.mercurial-scm.org/D867
author | Siddharth Agarwal <sid0@fb.com> |
---|---|
date | Sun, 01 Oct 2017 04:14:16 -0700 |
parents | |
children | e1c586b9a43c |
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""" Commonly useful converters. """ from __future__ import absolute_import, division, print_function def optional(converter): """ A converter that allows an attribute to be optional. An optional attribute is one which can be set to ``None``. :param callable converter: the converter that is used for non-``None`` values. .. versionadded:: 17.1.0 """ def optional_converter(val): if val is None: return None return converter(val) return optional_converter