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pythondecoratorkeyword-argument

How to replace Python function while supporting all passed in parameters

I'm looking for a way to decorate an arbitrary python function, so that an alternate function is called instead of the original, with all parameters passed as a list or dict.

More precisely, something like this (where f is any function, and replacement_f takes a list and a dict):

def replace_func(f, replacement_f):
    def new_f(*args, **kwargs):
        replacement_f(args, kwargs)
    return new_f

However, I cannot reference replacement_f inside new_f. And I can't use the standard trick of passing replacement_f to new_f as the default for a different parameter, because I'm using the *args and **kwargs variable argument lists.

The location where the original function is called cannot change, and will accept both positional and named parameters.

I fear that isn't very clear, but I'm happy to clarify if needed.

Thanks

Solution

  • why don't you just try:

    f = replacement_f

    example:

    >>> def rep(*args):
    print(*args, sep=' -- ')

>>> def ori(*args):
    print(args)

>>> ori('dfef', 32)
('dfef', 32)
>>> ori = rep
>>> ori('dfef', 32)
dfef -- 32