Question

Is there a possibility to check if two python functions are interchangeable? For instance, if I have

def foo(a, b):
    pass
def bar(x, y):
    pass
def baz(x,y,z):
    pass

I would like a function is_compatible(a,b) that returns True when passed foo and bar, but False when passed bar and baz, so I can check if they’re interchangeable before actually calling either of them.

Answer 1

Take a look at inspect.getargspec():

inspect.getargspec(func)

Get the names
and default values of a function’s
arguments. A tuple of four things is
returned: (args, varargs, varkw,
defaults). args is a list of the
argument names (it may contain nested
lists). varargs and varkw are the
names of the * and ** arguments or
None. defaults is a tuple of default
argument values or None if there are
no default arguments; if this tuple
has n elements, they correspond to the
last n elements listed in args.

Changed in version 2.6: Returns a
named tuple ArgSpec(args, varargs,
keywords, defaults).