How can I store a function with parameters as a variable without calling it immediately?

Question

I am creating a translator for my Raspberry Pi that will get an input, then output the Morse code with an LED.

I have a function that will accurately output the Morse code for the letter of my choosing. I am trying to assign the function with parameters to a variable for quicker access like this:

a = letter(dot, dash)

but when I try and store it like that it runs the function with those parameters, I also can't call it with something like a().

Answer 1

Yes, you can use partial for this:

from functools import partial

a = partial(letter, dot, dash)

Partial constructs a new function. If that function is called, it will call letter with dot and dash. In case you call a with parameters, those parameters are added at the end (the unnamed parameters), and the named parameters are updated.

Answer 2

You can set a variable to a function and then use the variable as the function's name. Here is an example:

def cube(number):    
    return number ** 3

make_cube = cube    # Take out those parentheses

Now, the variable make_cube can be used as a function, like so:

print(make_cube(2))
# 8

Both cube and make_cube point to the same memory address, which you can confirm with id(make_cube) == id(cube).

In your case, it can be:

a = letter
a(dot, dash)

Answer 3

You can also write the function expression as string and later on call using eval.

a = "letter(dot, dash)"
eval(a)

(Does not require importing of module)