Python decorator handling docstrings

Question

I have a problem using docstrings with decorators. Given the following example:

def decorator(f):
    def _decorator():
        print \'decorator active\'
           


        

Answer 1

I found a solution, but don't know if it's really nice:

def decorator(f):
    def _decorator():
        print 'decorator active'
        f()
    _decorator.__name__=f.__name__
    _decorator.__doc__=f.__doc__
    return _decorator

The part with _decorator.__name__=f.__name__ seems a little bit hideous... What do you think?

Answer 2

Take a look at functools.wraps: http://docs.python.org/library/functools.html

Answer 3

Use functools.wraps() to update the attributes of the decorator:

from functools import wraps

def decorator(f):
    @wraps(f)
    def _decorator():
        print 'decorator active'
        f()
    return _decorator

@decorator
def foo():
    '''the magic foo function'''
    print 'this is function foo'

help(foo)

Also see the Standard Library documentation for functools.