Implicit returns from single-expression functions
Implicit returns from single-expression functions 관련
Available from Swift 5.1
SE-0255 (apple/swift-evolution) has removed a small but important inconsistency in the language: single-expression functions that return a value can now remove the return keyword and Swift will understand it implicitly.
In previous versions of Swift, single-line closures that returned a value you could omit the return keyword because the only line of code that was there must be the one that returned a value. So, these two pieces of code were identical:
let doubled1 = [1, 2, 3].map { $0 * 2 }
let doubled2 = [1, 2, 3].map { return $0 * 2 }
In Swift 5.1, this behavior has now been extended to functions as well: if they contain a single expression – effectively a single piece of code that evaluates to a value – then you can leave off the return keyword, like this:
func double(_ number: Int) -> Int {
number * 2
}
That will probably cause some people to do a double take at first, but I’m sure it will become second nature over time.
Other Changes in Swift 5.1