#!/usr/bin/env python

# -*- coding: utf-8 -*-

"""

Reference: https://en.wikipedia.org/wiki/Delegation_pattern

Author: https://github.com/IuryAlves

*TL;DR80

Allows object composition to achieve the same code reuse as inheritance.

"""

class Delegator(object):

    """

    >>> delegator = Delegator(Delegate())

    >>> delegator.do_something("nothing")

    'Doing nothing'

    >>> delegator.do_anything()

    """

    def __init__(self, delegate):

        self.delegate = delegate

    def __getattr__(self, name):

        def wrapper(*args, **kwargs):

            if hasattr(self.delegate, name):

                attr = getattr(self.delegate, name)

                if callable(attr):

                    return attr(*args, **kwargs)

        return wrapper

class Delegate(object):

    def do_something(self, something):

        return "Doing %s" % something

if __name__ == '__main__':

    import doctest

    doctest.testmod()