Swift Programming: The Big Nerd Ranch Guide

Ternary Operator

The ternary operator is very similar to an if/else statement, but has more concise syntax. The syntax looks likes this: a ? b : c. In English, the ternary operator reads something like, “If a is true, then do b. Otherwise, do c.”

Let’s rewrite the town population check that used if/else using the ternary operator instead.

Listing 3.3  Using the ternary operator

...
if population < 10000 {
    message = "\(population) is a small town!"
} else {
    message = "\(population) is pretty big!"
}

message = population < 10000 ? "\(population) is a small town!" :
                     "\(population) is pretty big!"
...

The ternary operator can be a source of controversy: some programmers love it; some programmers loathe it. We come down somewhere ...