Return Values
Get an answer back from a function.
1func add(a: Int, b: Int) -> Int {
2 return a + b
3}
4
5print(add(a: 2, b: 3))
6print(add(a: 10, b: 20))
$ swift main.swift
5
30
Every line, explained
func add(a: Int, b: Int) -> Int {- func defines a function: your own named block of code. Defining it does nothing on its own; it waits until somebody calls it. In a Swift script, define a function before the line that calls it. The arrow -> Int says this function hands back an Int. Read the whole line as: "a function add that takes two Ints and returns an Int".
return a + b- return hands the value back to whoever called the function, and the function ends.
}- This } closes the function.
print(add(a: 2, b: 3))- add(a: 2, b: 3) runs the function and becomes its returned value: 5. Then print shows it.
print(add(a: 10, b: 20))- Same function, different inputs, different answer: 30.