Callback function syntax in Swift

Question

I am attempting pass a function to another function and then have the passed function executed passing to it a variable.

Here is my code:

func showSt         


        

Answer 1

You've declared callback to take no arguments, and then you're trying to pass it an argument.

You specified type (()->(String))?, which is an optional function that takes no arguments and returns a String.

Perhaps you mean to specify ((String)->())?, which is an optional function that takes a String and returns nothing.