python decorator with arguments of decorated function

Question

When I wrap a function with @, how do I make the wrapper function look & feel exactly like the wrapped function? help(function) in particular.<

Answer 1

functools.wraps can be used to copy the name and docstring of the function. Copying the original function signature is considerably harder to do from scratch.

If you use the third-party decorator module, however, then

import decorator


@decorator.decorator
def wraps(f):
    def call(*args, **kw):
        print('in', f, args, kw) 
        return f(*args, **kw)
    return call


def g():pass

@wraps
def f(a, b = 1, g = g, *args, **kw):
    pass

help(f)

yields

Help on function f in module __main__:

f(a, b=1, g=, *args, **kw)