Python: passing a function with parameters as parameter

Question

def lite(a,b,c):
    #...

def big(func): # func = callable()
    #...


#main
big(lite(1,2,3))

how to do this?
in what way to pass function with parameters to another function?

Answer 1

Why not do:

big(lite, (1, 2, 3))

?

Then you can do:

def big(func, args):
    func(*args)

Answer 2

import functools

#main
big(functools.partial(lite, 1,2,3))

Answer 3

Not this way, you're passing to big the return value of lite() function.

You should do something like:

def lite(a, b, c):
    return a + b + c

def big(func, arg):
    print func(arg[0], arg[1], arg[2])



big(lite, (1, 2, 3))

Answer 4

Similar problem is usually solved in two ways:

1. With lambda… but then the passed function will expect one argument, so big() needs to be changed
2. With named functions calling the original functions with arguments. Please note, that such function can be declared inside other function and the arguments can be variables.

See the example:

#!/usr/bin/python

def lite(a,b,c):
    return "%r,%r,%r" % (a,b,c)

def big(func): # func = callable()
    print func()

def big2(func): # func = callable with one argument
    print func("anything")


def main():
    param1 = 1
    param2 = 2
    param3 = 3

    big2(lambda x: lite(param1, param2, param3))

    def lite_with_params():
        return lite(param1,param2,param3)

    big(lite_with_params)

main()