On 04/27, Makoto Kuwata wrote:
>
> I feel that function decorator having arguments is complicated,
> because three 'def' are nested:
>
> def multiply(n):
> def deco(func):
> def newfunc(*args, **kwargs):
> return n * func(*args, **kwargs)
> return newfunc
> return deco
When I have to write an argument-taking decorator, I use a class:
class multiply(object): # don't need 'object in 3.x'
def __init__(self, n):
self.n = n
def __call__(self, func):
def newfunc(*args, **kwargs):
return self.n * func(*args, **kwargs)
return newfunc
> @multiply(4)
> def f1(x, y):
> return x+y
>
> print(f1(2, 3)) #=> 20 (= 4 * (2+3))
This all works the same.
>
>
> If function decorator notation could take arguments,
> decorator definition would be more simple:
>
> def multiply(func, n):
> def newfunc(*args, **kwargs):
> return n * func(*args, **kwargs)
> return newfunc
>
> @multiply 4 # ex: @decorator arg1, arg2, arg3
> def f1(x, y):
> return x+y
>
>
> How do you think about this idea?
It's unnecessary, just use a class instead of a function to get more
clarity.
--
~Ethan~
--
https://mail.python.org/mailman/listinfo/python-list
