Calling functions one by one from a python list

Question

I have a list of functions say

list1 = ['foo','boo','koo']

now I want to call these functions one by one.

for i in range(len(list1)):
    list1[i](<argumentslist>)

This gives me an error:

TypeError: 'str' object is not callable

How Should I make this possible ?

"I have a list of functions" -- Not exactly, it looks like you have a list of strings. How you convert those strings to functions depends on a lot of things but my guess is that it'll probably involve either using `getattr` or `globals` (Or, you could actually create a list of functions rather than a list of strings that represent functions in one way or another). — mgilson, Aug 07 '17 at 13:18
Not again. This is technically possible, but it is **very bad design**... Call-by-name is very insecure — Willem Van Onsem, Aug 07 '17 at 13:18
You need to use a list of actual functions -eg. `list1 = [foo,boo,koo]`, not a list of names of functions — Gerrat, Aug 07 '17 at 13:20
Possible duplicate of [Calling a function of a module from a string with the function's name in Python](https://stackoverflow.com/questions/3061/calling-a-function-of-a-module-from-a-string-with-the-functions-name-in-python) — voodoo-burger, Aug 07 '17 at 13:21
Possible duplicate of [Calling functions from a list issue](https://stackoverflow.com/questions/22875834/calling-functions-from-a-list-issue) — Ajax1234, Aug 07 '17 at 13:34

score 0 · Answer 1 · answered Aug 07 '17 at 13:20

0

Drop the ' in the list

list1 = [foo,boo,koo]

answered Aug 07 '17 at 13:20

damisan

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score 0 · Answer 2 · answered Aug 07 '17 at 13:22

0

Your list is does not contain a function objects, you are storing a string. Functions are first class object in python. If you want to store it as a list and call them use the function object as follows. list = [foo, bar ] list[0](args)

answered Aug 07 '17 at 13:22

NishanthSpShetty

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score 0 · Answer 3 · answered Aug 07 '17 at 13:23

0

Currently the elements in your list are strings. Given that you have defined functions foo, boo, koo you can put these in a list without the' surrounding them. I.e. you will be making a list of functions, not a list of string function names.

answered Aug 07 '17 at 13:23

Bruno KM

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score 0 · Answer 4 · answered Aug 07 '17 at 13:23

0

Not recommended but:

def hello_world(int_):
    print("hello{}".format(int_))

list_ = ["hello_world"]
arg = 2

for i in list_:
    exec("{}({})".format(i,arg))

#hello2

answered Aug 07 '17 at 13:23

Anton vBR

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score 0 · Answer 5 · answered Aug 07 '17 at 13:26

You do not have to remove the quotes if you use **kwargs:

def the_function(**functions): 

    list1 = ['foo','boo','koo']
    for i in range(len(list1)):
        val = functions[list1[i]](3)

f1 = lambda x: pow(x, 2)
f2 = lambda x: x+3
f3 = lambda x: sum(i for i in range(x))

the_function(foo = f1, boo = f2, koo = f3)

Calling functions one by one from a python list

5 Answers5