propcache
May 8, 2026 · View on GitHub
The module provides a fast implementation of cached properties for Python 3.10+.
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Introduction
The API is designed to be nearly identical to the built-in functools.cached_property class,
except for the additional under_cached_property class which uses self._cache
instead of self.__dict__ to store the cached values and prevents __set__ from being called.
For full documentation please read https://propcache.readthedocs.io.
Installation
::
$ pip install propcache
The library is Python 3 only!
PyPI contains binary wheels for Linux, Windows and MacOS. If you want to install
propcache on another operating system where wheels are not provided,
the the tarball will be used to compile the library from
the source code. It requires a C compiler and and Python headers installed.
To skip the compilation you must explicitly opt-in by using a PEP 517
configuration setting pure-python, or setting the PROPCACHE_NO_EXTENSIONS
environment variable to a non-empty value, e.g.:
.. code-block:: console
$ pip install propcache --config-settings=pure-python=false
Please note that the pure-Python (uncompiled) version is much slower. However, PyPy always uses a pure-Python implementation, and, as such, it is unaffected by this variable.
API documentation
The documentation is located at https://propcache.readthedocs.io.
Source code
The project is hosted on GitHub_
Please file an issue on the bug tracker <https://github.com/aio-libs/propcache/issues>_ if you have found a bug
or have some suggestion in order to improve the library.
Discussion list
aio-libs google group: https://groups.google.com/forum/#!forum/aio-libs
Feel free to post your questions and ideas here.
Authors and License
The propcache package is derived from yarl which is written by Andrew Svetlov.
It's Apache 2 licensed and freely available.
.. _GitHub: https://github.com/aio-libs/propcache