Metadata-Version: 2.1
Name: attrs
Version: 21.4.0
Summary: Classes Without Boilerplate
Home-page: https://www.attrs.org/
Author: Hynek Schlawack
Author-email: hs@ox.cx
Maintainer: Hynek Schlawack
Maintainer-email: hs@ox.cx
License: MIT
Project-URL: Documentation, https://www.attrs.org/
Project-URL: Changelog, https://www.attrs.org/en/stable/changelog.html
Project-URL: Bug Tracker, https://github.com/python-attrs/attrs/issues
Project-URL: Source Code, https://github.com/python-attrs/attrs
Project-URL: Funding, https://github.com/sponsors/hynek
Project-URL: Tidelift, https://tidelift.com/subscription/pkg/pypi-attrs?utm_source=pypi-attrs&utm_medium=pypi
Project-URL: Ko-fi, https://ko-fi.com/the_hynek
Keywords: class,attribute,boilerplate
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: Natural Language :: English
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Requires-Python: >=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*
Description-Content-Type: text/x-rst
License-File: LICENSE
License-File: AUTHORS.rst
Provides-Extra: dev
Requires-Dist: coverage[toml] (>=5.0.2) ; extra == 'dev'
Requires-Dist: hypothesis ; extra == 'dev'
Requires-Dist: pympler ; extra == 'dev'
Requires-Dist: pytest (>=4.3.0) ; extra == 'dev'
Requires-Dist: six ; extra == 'dev'
Requires-Dist: mypy ; extra == 'dev'
Requires-Dist: pytest-mypy-plugins ; extra == 'dev'
Requires-Dist: zope.interface ; extra == 'dev'
Requires-Dist: furo ; extra == 'dev'
Requires-Dist: sphinx ; extra == 'dev'
Requires-Dist: sphinx-notfound-page ; extra == 'dev'
Requires-Dist: pre-commit ; extra == 'dev'
Requires-Dist: cloudpickle ; (platform_python_implementation == "CPython") and extra == 'dev'
Provides-Extra: docs
Requires-Dist: furo ; extra == 'docs'
Requires-Dist: sphinx ; extra == 'docs'
Requires-Dist: zope.interface ; extra == 'docs'
Requires-Dist: sphinx-notfound-page ; extra == 'docs'
Provides-Extra: tests
Requires-Dist: coverage[toml] (>=5.0.2) ; extra == 'tests'
Requires-Dist: hypothesis ; extra == 'tests'
Requires-Dist: pympler ; extra == 'tests'
Requires-Dist: pytest (>=4.3.0) ; extra == 'tests'
Requires-Dist: six ; extra == 'tests'
Requires-Dist: mypy ; extra == 'tests'
Requires-Dist: pytest-mypy-plugins ; extra == 'tests'
Requires-Dist: zope.interface ; extra == 'tests'
Requires-Dist: cloudpickle ; (platform_python_implementation == "CPython") and extra == 'tests'
Provides-Extra: tests_no_zope
Requires-Dist: coverage[toml] (>=5.0.2) ; extra == 'tests_no_zope'
Requires-Dist: hypothesis ; extra == 'tests_no_zope'
Requires-Dist: pympler ; extra == 'tests_no_zope'
Requires-Dist: pytest (>=4.3.0) ; extra == 'tests_no_zope'
Requires-Dist: six ; extra == 'tests_no_zope'
Requires-Dist: mypy ; extra == 'tests_no_zope'
Requires-Dist: pytest-mypy-plugins ; extra == 'tests_no_zope'
Requires-Dist: cloudpickle ; (platform_python_implementation == "CPython") and extra == 'tests_no_zope'


.. image:: https://www.attrs.org/en/stable/_static/attrs_logo.png
   :alt: attrs logo
   :align: center


``attrs`` is the Python package that will bring back the **joy** of **writing classes** by relieving you from the drudgery of implementing object protocols (aka `dunder methods <https://www.attrs.org/en/latest/glossary.html#term-dunder-methods>`_).
`Trusted by NASA <https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-github-profile/customizing-your-profile/personalizing-your-profile#list-of-qualifying-repositories-for-mars-2020-helicopter-contributor-badge>`_ for Mars missions since 2020!

Its main goal is to help you to write **concise** and **correct** software without slowing down your code.

.. teaser-end

For that, it gives you a class decorator and a way to declaratively define the attributes on that class:

.. -code-begin-

.. code-block:: pycon

   >>> from attrs import asdict, define, make_class, Factory

   >>> @define
   ... class SomeClass:
   ...     a_number: int = 42
   ...     list_of_numbers: list[int] = Factory(list)
   ...
   ...     def hard_math(self, another_number):
   ...         return self.a_number + sum(self.list_of_numbers) * another_number


   >>> sc = SomeClass(1, [1, 2, 3])
   >>> sc
   SomeClass(a_number=1, list_of_numbers=[1, 2, 3])

   >>> sc.hard_math(3)
   19
   >>> sc == SomeClass(1, [1, 2, 3])
   True
   >>> sc != SomeClass(2, [3, 2, 1])
   True

   >>> asdict(sc)
   {'a_number': 1, 'list_of_numbers': [1, 2, 3]}

   >>> SomeClass()
   SomeClass(a_number=42, list_of_numbers=[])

   >>> C = make_class("C", ["a", "b"])
   >>> C("foo", "bar")
   C(a='foo', b='bar')


After *declaring* your attributes ``attrs`` gives you:

- a concise and explicit overview of the class's attributes,
- a nice human-readable ``__repr__``,
- a equality-checking methods,
- an initializer,
- and much more,

*without* writing dull boilerplate code again and again and *without* runtime performance penalties.

**Hate type annotations**!?
No problem!
Types are entirely **optional** with ``attrs``.
Simply assign ``attrs.field()`` to the attributes instead of annotating them with types.

----

This example uses ``attrs``'s modern APIs that have been introduced in version 20.1.0, and the ``attrs`` package import name that has been added in version 21.3.0.
The classic APIs (``@attr.s``, ``attr.ib``, plus their serious business aliases) and the ``attr`` package import name will remain **indefinitely**.

Please check out `On The Core API Names <https://www.attrs.org/en/latest/names.html>`_ for a more in-depth explanation.


Data Classes
============

On the tin, ``attrs`` might remind you of ``dataclasses`` (and indeed, ``dataclasses`` are a descendant of ``attrs``).
In practice it does a lot more and is more flexible.
For instance it allows you to define `special handling of NumPy arrays for equality checks <https://www.attrs.org/en/stable/comparison.html#customization>`_, or allows more ways to `plug into the initialization process <https://www.attrs.org/en/stable/init.html#hooking-yourself-into-initialization>`_.

For more details, please refer to our `comparison page <https://www.attrs.org/en/stable/why.html#data-classes>`_.


.. -getting-help-

Getting Help
============

Please use the ``python-attrs`` tag on `Stack Overflow <https://stackoverflow.com/questions/tagged/python-attrs>`_ to get help.

Answering questions of your fellow developers is also a great way to help the project!


.. -project-information-

Project Information
===================

``attrs`` is released under the `MIT <https://choosealicense.com/licenses/mit/>`_ license,
its documentation lives at `Read the Docs <https://www.attrs.org/>`_,
the code on `GitHub <https://github.com/python-attrs/attrs>`_,
and the latest release on `PyPI <https://pypi.org/project/attrs/>`_.
It’s rigorously tested on Python 2.7, 3.5+, and PyPy.

We collect information on **third-party extensions** in our `wiki <https://github.com/python-attrs/attrs/wiki/Extensions-to-attrs>`_.
Feel free to browse and add your own!

If you'd like to contribute to ``attrs`` you're most welcome and we've written `a little guide <https://github.com/python-attrs/attrs/blob/main/.github/CONTRIBUTING.md>`_ to get you started!


``attrs`` for Enterprise
------------------------

Available as part of the Tidelift Subscription.

The maintainers of ``attrs`` and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source packages you use to build your applications.
Save time, reduce risk, and improve code health, while paying the maintainers of the exact packages you use.
`Learn more. <https://tidelift.com/subscription/pkg/pypi-attrs?utm_source=pypi-attrs&utm_medium=referral&utm_campaign=enterprise&utm_term=repo>`_


Release Information
===================

21.4.0 (2021-12-29)
-------------------

Changes
^^^^^^^

- Fixed the test suite on PyPy3.8 where ``cloudpickle`` does not work.
  `#892 <https://github.com/python-attrs/attrs/issues/892>`_
- Fixed ``coverage report`` for projects that use ``attrs`` and don't set a ``--source``.
  `#895 <https://github.com/python-attrs/attrs/issues/895>`_,
  `#896 <https://github.com/python-attrs/attrs/issues/896>`_

`Full changelog <https://www.attrs.org/en/stable/changelog.html>`_.

Credits
=======

``attrs`` is written and maintained by `Hynek Schlawack <https://hynek.me/>`_.

The development is kindly supported by `Variomedia AG <https://www.variomedia.de/>`_.

A full list of contributors can be found in `GitHub's overview <https://github.com/python-attrs/attrs/graphs/contributors>`_.

It’s the spiritual successor of `characteristic <https://characteristic.readthedocs.io/>`_ and aspires to fix some of it clunkiness and unfortunate decisions.
Both were inspired by Twisted’s `FancyEqMixin <https://twistedmatrix.com/documents/current/api/twisted.python.util.FancyEqMixin.html>`_ but both are implemented using class decorators because `subclassing is bad for you <https://www.youtube.com/watch?v=3MNVP9-hglc>`_, m’kay?