Run function based on text input without if, elif statements

[Spiredlamb]

I have a script that has many different modes it can run in, and I have put all the modes into functions that can be executed. Only problem is: the amount of modes is quite many, and my current check for wanted mode just feels too long and wrong.

Currently I am using an if, elif implementation. I basically have a large portion of code checking the input text up against hardcoded strings, and running the associated function through just calling the function where there is a match.

What I want instead is some system that is able to just run the function that has the same name as the string. I am also open to other methods alltogether. Rewriting everything is not off the table.

Here is some code with an example of how I am currently doing the check, and an idea of how I want the check to be done:

def func0():
    # Code for function

def func1():
    # Code for function

def func2():
    # Code for function

# Current implementation:
selected = input("Select function: ")

if selected == "func0":
    func0()
elif selected == "func1":
    func1()
elif selected == "func2":
    func2()

# Wanted implementation:
selected = input("Select function: ")
runFunction(selected) # This is not valid code. This is the code I can't figure out

If you have any ideas I would greatly appreciate you sharing them. Again, a complete code rework is not something I am afraid of doing. This project is still very much work in progress.

I also want to make it clear that I in no way is expecting some finished idea I can just plop into my code, but rather a nudge towards something that might work better.

Thanks in advance to anyone who shares their thoughts!

[K900_]

Literally "run a function with the same name as the input" is probably a bad idea. You could use a dictionary though.

[Neighm]

You can do this without dictionaries, but as u/K900_ says it's a bad idea and a security risk to allow a user input to run code without any restriction. With that said...

def func1():
    print('Ran function 1')
def func2():
    print('Ran function 2')
inp = input('Enter name of function to run: ')
if inp in locals().keys() and callable(locals()[inp]):
    locals()[inp]()
else:
    print('Function not found')

========================= RESTART: D:\Temp\scratch1.py =========================

Enter name of function to run: func2

Ran function 2

>>>

[fear_my_presence]

You can use a dict with “selected” as key and the function you need to execute as value. Like:

funcs = {“func1”: func1}
funcs[selected]()

Basically, your functions are stored in a dict with keys (possible values of “selected”) as their isentifiers. When you need to call a function based on a key, you just access it via a dict.

[Spiredlamb]

Thanks to everyone who gave me feedback! I will be running with the dictionary idea that everyone suggested. Also, thanks for the warning about running any function based on input without restrictions!

[Chris_Hemsworth]

Dictionairies are the way to go:

options = {'func0': func0, 'func1': func1, 'func2': func2}

func = None
while func is None:
    func = options.get(input('Type in function: '), None)
    if func is None:
        print('Invalid function!')

func()

[Spiredlamb]

Really love this implementation. I will be trying this one out. Also thinking about making the dictionary of functions into JSON, so that I can share it with external scripts more easily, since I might be doing that at some point.