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
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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'
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