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========
Overview
========
.. start-badges
.. list-table::
:stub-columns: 1
* - docs
- |docs|
* - tests
- | |github-actions|
| |coveralls| |codecov|
* - package
- | |version| |wheel| |supported-versions| |supported-implementations|
| |commits-since|
.. |docs| image:: https://readthedocs.org/projects/python-lazy-object-proxy/badge/?style=flat
:target: https://python-lazy-object-proxy.readthedocs.io/
:alt: Documentation Status
.. |github-actions| image:: https://github.com/ionelmc/python-lazy-object-proxy/actions/workflows/github-actions.yml/badge.svg
:alt: GitHub Actions Build Status
:target: https://github.com/ionelmc/python-lazy-object-proxy/actions
.. |coveralls| image:: https://coveralls.io/repos/github/ionelmc/python-lazy-object-proxy/badge.svg?branch=master
:alt: Coverage Status
:target: https://coveralls.io/github/ionelmc/python-lazy-object-proxy?branch=master
.. |codecov| image:: https://codecov.io/gh/ionelmc/python-lazy-object-proxy/branch/master/graphs/badge.svg?branch=master
:alt: Coverage Status
:target: https://app.codecov.io/github/ionelmc/python-lazy-object-proxy
.. |version| image:: https://img.shields.io/pypi/v/lazy-object-proxy.svg
:alt: PyPI Package latest release
:target: https://pypi.org/project/lazy-object-proxy
.. |wheel| image:: https://img.shields.io/pypi/wheel/lazy-object-proxy.svg
:alt: PyPI Wheel
:target: https://pypi.org/project/lazy-object-proxy
.. |supported-versions| image:: https://img.shields.io/pypi/pyversions/lazy-object-proxy.svg
:alt: Supported versions
:target: https://pypi.org/project/lazy-object-proxy
.. |supported-implementations| image:: https://img.shields.io/pypi/implementation/lazy-object-proxy.svg
:alt: Supported implementations
:target: https://pypi.org/project/lazy-object-proxy
.. |commits-since| image:: https://img.shields.io/github/commits-since/ionelmc/python-lazy-object-proxy/v1.10.0.svg
:alt: Commits since latest release
:target: https://github.com/ionelmc/python-lazy-object-proxy/compare/v1.10.0...master
.. end-badges
A fast and thorough lazy object proxy.
* Free software: BSD 2-Clause License
Note that this is based on `wrapt`_'s ObjectProxy with one big change: it calls a function the first time the proxy object is
used, while `wrapt.ObjectProxy` just forwards the method calls to the target object.
In other words, you use `lazy-object-proxy` when you only have the object way later and you use `wrapt.ObjectProxy` when you
want to override few methods (by subclassing) and forward everything else to the target object.
Example::
import lazy_object_proxy
def expensive_func():
from time import sleep
print('starting calculation')
# just as example for a very slow computation
sleep(2)
print('finished calculation')
# return the result of the calculation
return 10
obj = lazy_object_proxy.Proxy(expensive_func)
# function is called only when object is actually used
print(obj) # now expensive_func is called
print(obj) # the result without calling the expensive_func
Installation
============
::
pip install lazy-object-proxy
Documentation
=============
https://python-lazy-object-proxy.readthedocs.io/
Development
===========
To run all the tests run::
tox
Acknowledgements
================
This project is based on some code from `wrapt`_ as you can see in the git history.
.. _wrapt: https://github.com/GrahamDumpleton/wrapt
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