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xpostudio4/decorators_cheat_sheet.py

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  1. xpostudio4 renamed this gist Feb 23, 2015. 1 changed file with 0 additions and 0 deletions.
    0 decorators CheatSheet → decorators_cheat_sheet.py
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  2. xpostudio4 renamed this gist Feb 23, 2015. 1 changed file with 0 additions and 0 deletions.
    0 gistfile1.py → decorators CheatSheet
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  3. xpostudio4 created this gist Feb 23, 2015.
    109 changes: 109 additions & 0 deletions gistfile1.py
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    import functools # Part of Python standard library

    def decorator(wrapped_function):
    def _wrapper(*args, **kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call
    return result
    return _wrapper

    # decorator with functools.wraps added
    def decorator_with_wraps(wrapped_function):
    @functools.wraps(wrapped_function)
    def _wrapper(*args, **kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call
    return result
    return _wrapper

    import wrapt # Requires installing the 'wrapt' library

    # decorator powered by wrapt
    @wrapt.decorator
    def decorator_with_wrapt(wrapped_function, instance, args, kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call
    return result

    def test_decorators():

    @decorator
    def func1():
    return 'I'

    @decorator_with_wraps
    def func2():
    return 'code'

    @decorator_with_wrapt
    def func3():
    return 'python'

    assert func1() == 'I'
    assert func2() == 'code'
    assert func3() == 'python'

    #decorators that accept arguments
    def arguments_decorator(arg1, arg2):
    def _outer_wrapper(wrapped_function):
    def _wrapper(*args, **kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call

    # Demonstrating what you can do with decorator arguments
    result = result * arg1 * arg2

    return result
    return _wrapper
    return _outer_wrapper

    def arguments_decorator_with_wraps(arg1, arg2):
    def _outer_wrapper(wrapped_function):
    @functools.wraps(wrapped_function)
    def _wrapper(*args, **kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call

    # Demonstrating what you can do with decorator arguments
    result = result * arg1 * arg2

    return result
    return _wrapper
    return _outer_wrapper

    def arguments_decorator_with_wrapt(arg1, arg2):
    @wrapt.decorator
    def _wrapper(wrapped_function, instance, args, kwargs):
    # do something before the function call
    result = wrapped_function(*args, **kwargs)
    # do something after the function call

    # Demonstrating what you can do with decorator arguments
    result = result * arg1 * arg2

    return result
    return _wrapper


    def test_arguments_decorators():

    @arguments_decorator(2, 3)
    def func4():
    return 'We'

    @arguments_decorator_with_wraps(2, 2)
    def func5():
    return 'code'

    @arguments_decorator_with_wrapt(3, 2)
    def func6():
    return 'python'

    assert func4() == 'WeWeWeWeWeWe'
    assert func5() == 'codecodecodecode'
    assert func6() == 'pythonpythonpythonpythonpythonpython'