1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
|
Metadata-Version: 2.1
Name: attrs
Version: 23.1.0
Summary: Classes Without Boilerplate
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
Author-email: Hynek Schlawack <hs@ox.cx>
License-Expression: MIT
License-File: LICENSE
Keywords: attribute,boilerplate,class
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: MIT License
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 :: 3.11
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Classifier: Typing :: Typed
Requires-Python: >=3.7
Requires-Dist: importlib-metadata; python_version < '3.8'
Provides-Extra: cov
Requires-Dist: attrs[tests]; extra == 'cov'
Requires-Dist: coverage[toml]>=5.3; extra == 'cov'
Provides-Extra: dev
Requires-Dist: attrs[docs,tests]; extra == 'dev'
Requires-Dist: pre-commit; extra == 'dev'
Provides-Extra: docs
Requires-Dist: furo; extra == 'docs'
Requires-Dist: myst-parser; extra == 'docs'
Requires-Dist: sphinx; extra == 'docs'
Requires-Dist: sphinx-notfound-page; extra == 'docs'
Requires-Dist: sphinxcontrib-towncrier; extra == 'docs'
Requires-Dist: towncrier; extra == 'docs'
Requires-Dist: zope-interface; extra == 'docs'
Provides-Extra: tests
Requires-Dist: attrs[tests-no-zope]; extra == 'tests'
Requires-Dist: zope-interface; extra == 'tests'
Provides-Extra: tests-no-zope
Requires-Dist: cloudpickle; platform_python_implementation == 'CPython' and extra == 'tests-no-zope'
Requires-Dist: hypothesis; extra == 'tests-no-zope'
Requires-Dist: mypy>=1.1.1; platform_python_implementation == 'CPython' and extra == 'tests-no-zope'
Requires-Dist: pympler; extra == 'tests-no-zope'
Requires-Dist: pytest-mypy-plugins; platform_python_implementation == 'CPython' and python_version < '3.11' and extra == 'tests-no-zope'
Requires-Dist: pytest-xdist[psutil]; extra == 'tests-no-zope'
Requires-Dist: pytest>=4.3.0; extra == 'tests-no-zope'
Description-Content-Type: text/markdown
<p align="center">
<a href="https://www.attrs.org/">
<img src="https://raw.githubusercontent.com/python-attrs/attrs/main/docs/_static/attrs_logo.svg" width="35%" alt="attrs" />
</a>
</p>
*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-achievement) for Mars missions since 2020!
Its main goal is to help you to write **concise** and **correct** software without slowing down your code.
## Sponsors
*attrs* would not be possible without our [amazing sponsors](https://github.com/sponsors/hynek).
Especially those generously supporting us at the *The Organization* tier and higher:
<p align="center">
<a href="https://www.variomedia.de/">
<img src="https://raw.githubusercontent.com/python-attrs/attrs/main/.github/sponsors/Variomedia.svg" width="200" height="60"></img>
</a>
<a href="https://tidelift.com/subscription/pkg/pypi-attrs?utm_source=pypi-attrs&utm_medium=referral&utm_campaign=enterprise&utm_term=repo">
<img src="https://raw.githubusercontent.com/python-attrs/attrs/main/.github/sponsors/Tidelift.svg" width="200" height="60"></img>
</a>
<a href="https://sentry.io/">
<img src="https://raw.githubusercontent.com/python-attrs/attrs/main/.github/sponsors/Sentry.svg" width="200" height="60"></img>
</a>
<a href="https://filepreviews.io/">
<img src="https://raw.githubusercontent.com/python-attrs/attrs/main/.github/sponsors/FilePreviews.svg" width="200" height="60"></img>
</a>
</p>
<p align="center">
<strong>Please consider <a href="https://github.com/sponsors/hynek">joining them</a> to help make <em>attrs</em>’s maintenance more sustainable!</strong>
</p>
<!-- teaser-end -->
## Example
*attrs* gives you a class decorator and a way to declaratively define the attributes on that class:
<!-- code-begin -->
```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__`,
- 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](https://hynek.me/articles/import-attrs/) 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).
## Project Information
- [**Changelog**](https://www.attrs.org/en/stable/changelog.html)
- [**Documentation**](https://www.attrs.org/)
- [**PyPI**](https://pypi.org/project/attrs/)
- [**Source Code**](https://github.com/python-attrs/attrs)
- [**Contributing**](https://github.com/python-attrs/attrs/blob/main/.github/CONTRIBUTING.md)
- [**Third-party Extensions**](https://github.com/python-attrs/attrs/wiki/Extensions-to-attrs)
- **License**: [MIT](https://www.attrs.org/en/latest/license.html)
- **Get Help**: please use the `python-attrs` tag on [StackOverflow](https://stackoverflow.com/questions/tagged/python-attrs)
- **Supported Python Versions**: 3.7 and later
### *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
### Backwards-incompatible Changes
- Python 3.6 has been dropped and packaging switched to static package data using [Hatch](https://hatch.pypa.io/latest/).
[#993](https://github.com/python-attrs/attrs/issues/993)
### Deprecations
- The support for *zope-interface* via the `attrs.validators.provides` validator is now deprecated and will be removed in, or after, April 2024.
The presence of a C-based package in our developement dependencies has caused headaches and we're not under the impression it's used a lot.
Let us know if you're using it and we might publish it as a separate package.
[#1120](https://github.com/python-attrs/attrs/issues/1120)
### Changes
- `attrs.filters.exclude()` and `attrs.filters.include()` now support the passing of attribute names as strings.
[#1068](https://github.com/python-attrs/attrs/issues/1068)
- `attrs.has()` and `attrs.fields()` now handle generic classes correctly.
[#1079](https://github.com/python-attrs/attrs/issues/1079)
- Fix frozen exception classes when raised within e.g. `contextlib.contextmanager`, which mutates their `__traceback__` attributes.
[#1081](https://github.com/python-attrs/attrs/issues/1081)
- `@frozen` now works with type checkers that implement [PEP-681](https://peps.python.org/pep-0681/) (ex. [pyright](https://github.com/microsoft/pyright/)).
[#1084](https://github.com/python-attrs/attrs/issues/1084)
- Restored ability to unpickle instances pickled before 22.2.0.
[#1085](https://github.com/python-attrs/attrs/issues/1085)
- `attrs.asdict()`'s and `attrs.astuple()`'s type stubs now accept the `attrs.AttrsInstance` protocol.
[#1090](https://github.com/python-attrs/attrs/issues/1090)
- Fix slots class cellvar updating closure in CPython 3.8+ even when `__code__` introspection is unavailable.
[#1092](https://github.com/python-attrs/attrs/issues/1092)
- `attrs.resolve_types()` can now pass `include_extras` to `typing.get_type_hints()` on Python 3.9+, and does so by default.
[#1099](https://github.com/python-attrs/attrs/issues/1099)
- Added instructions for pull request workflow to `CONTRIBUTING.md`.
[#1105](https://github.com/python-attrs/attrs/issues/1105)
- Added *type* parameter to `attrs.field()` function for use with `attrs.make_class()`.
Please note that type checkers ignore type metadata passed into `make_class()`, but it can be useful if you're wrapping _attrs_.
[#1107](https://github.com/python-attrs/attrs/issues/1107)
- It is now possible for `attrs.evolve()` (and `attr.evolve()`) to change fields named `inst` if the instance is passed as a positional argument.
Passing the instance using the `inst` keyword argument is now deprecated and will be removed in, or after, April 2024.
[#1117](https://github.com/python-attrs/attrs/issues/1117)
- `attrs.validators.optional()` now also accepts a tuple of validators (in addition to lists of validators).
[#1122](https://github.com/python-attrs/attrs/issues/1122)
---
[Full changelog](https://www.attrs.org/en/stable/changelog.html)
|
