In Python, is it possible to accept a function call template as a parameter?

Question

As part of improving the syntax for Aspect-Oriented Programming in Python based on the excellent answer by jsbueno: Aspect oriented programming (AOP) in Python , I was wondering if it's possible to accept a function template as a parameter in Python with any decoration.

Eg, being able to call foo(bar(5)) with bar undefined, and have foo receive an object representing the expression bar(5) ; rather than an error that bar is undefined. (This would then be used as an input to construct a rule for matching incoming network messages indicating that another node has run function bar with parameter 5.)

Is there any better way to do this than passing the template as a string and parsing it with ast ?

Answer 1

I am not exactly sure, what your looking for, maybe this will help:

def decorator(f):
    def wrapper(*args, **kwargs):
        print("f in wraper with: {}".format(f.__defaults__))
        return f(*args, **kwargs)
    return wrapper

funcs = {}
fdefaults = [1, 2, 3]
code = """def myfunc(x={}): return print("f returning:", *x)""".format(fdefaults)

exec(code, {}, funcs)
myfunc = decorator(funcs["myfunc"])
myfunc()

outputs: f in wraper with: ([1, 2, 3],) f returning: 1 2 3