functools.wraps

我们在使用 Decorator 的过程中，难免会损失一些原本的功能信息。直接拿 stackoverflow 里面的栗子

 

 

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def logged(func):     def with_logging(*args, **kwargs):         print func.__name__ + " was called"         return func(*args, **kwargs)     return with_logging   @logged def f(x):    """does some math"""    return x + x * x   def f(x):     """does some math"""     return x + x * x f = logged(f)   In [24]: f.__name__ Out[24]: with_logging

而functools.wraps 则可以将原函数对象的指定属性复制给包装函数对象, 默认有 __module__、__name__、__doc__,或者通过参数选择。代码如下：

 

 

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from functools import wraps def logged(func):     @wraps(func)     def with_logging(*args, **kwargs):         print func.__name__ + " was called"         return func(*args, **kwargs)     return with_logging   @logged def f(x):    """does some math"""    return x + x * x   print f.__name__  # prints 'f'