How do you use a string from a list to call a function with the same name, in Python?

Question

I wasn't able to find a satisfying answer anywhere so I decided to ask.

Let's say we have a global counter and a global list

counter=0
list=["function1","function2",..."functionN"]

we also we have those functions defined:

def function1():
  pass
def function2():
  pass
.
.
.
def functionN():
  pass

I have an interface with a button, every time I press it, the global counter increments. Depending on the number, I need to call a different function. I can implement this with if and elif but I don't think it's that smart. Is there a way I can call those functions using the list?

Example

when counter=0=>list[0]=>the string is 'function1'=> call function1()

press button again

counter=1=>list[1]=>the string is 'function2' => call function2()

Why do we have a list of strings, rather than a list of functions [function1, function2, ...] so that I can just call list[counter]() directly? — chepner
– chepner, Commented Feb 28, 2020 at 19:59

Quinn · Accepted Answer · 2020-02-28 19:49:32Z

3

You can call a function by its name like this:

locals()["myfunction"]()

or:

globals()["myfunction"]()

or if its from another module like this:

import foo
getattr(foo, 'myfunction')()

Or if it suits your use case, just use a list of functions instead of a list of strings:

def func1():
    print("1")

def func2():
    print("2")

def func3():
    print("3")

def func4():
    print("4")

some_list=[func1, func2, func3, func4]

# call like this
for f in some_list:
    f()

# or like this
some_list[0]()

edited Feb 28, 2020 at 19:49

answered Feb 28, 2020 at 19:43

Quinn

9,8989 gold badges43 silver badges70 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

roarkz · Accepted Answer · 2020-02-28 20:56:39Z

1

Similar to what @chepner said, I would approach the problem that way.

Potentially storing the functions in a dictionary and looking up the function based on the counter:

def function():
    print('function 1 called')

def function2():
    print('function 2 called')

counter = 0

functions = {
    1: function,
    2: function2
}

Then:

function_to_call = functions[counter + 1]

and now that when function_to_call() is called it would print function 1 called

This is how I would think about approaching the problem.

answered Feb 28, 2020 at 20:56

roarkz

83112 silver badges22 bronze badges

Collectives™ on Stack Overflow

How do you use a string from a list to call a function with the same name, in Python?

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related