iOS Programming: The Big Nerd Ranch Guide

Loops and String Interpolation

Swift has all the control flow statements that you may be familiar with from other languages: if-else, while, for, for-in, repeat-while, and switch. Even if they are familiar, however, there may be some differences from what you are accustomed to. The key difference between these statements in Swift and in C-like languages is that while enclosing parentheses are not necessary on these statements’ expressions, Swift does require braces on clauses. Additionally, the expressions for if and while-like statements must evaluate to a Bool.

Consider this very traditional C-style loop, written in Swift:

for var i = 0; i < countingUp.count; ++i {
    let string = countingUp[i]
    // Use 'string'
}

You could ...