AS3, remove function

Good day!

I was wondering, if you make a function and you call it in another function as
“createLines(textBlock);” how do you remove it again?

I know if you call a function as bla.addEventListener(…); and you say bla.removeEventListener(…); but I don’t know If you just call a function as functionName();

Thank you very much.

Nellis Basson