========
Overview
========

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    :target: https://requires.io/github/ionelmc/python-lazy-object-proxy/requirements/?branch=master

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    :alt: Coverage Status
    :target: https://codecov.io/github/ionelmc/python-lazy-object-proxy

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    :target: https://pypi.org/project/lazy-object-proxy

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    :target: https://pypi.org/project/lazy-object-proxy

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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