Почему sorted() работает, а sort() нет?
let luckyNumbers = [7, 4, 38, 21, 16, 15, 12, 33, 31, 49]
luckyNumbers.filter { $0 % 2 != 0 }.sorted().map { "\($0) is lucky" }.forEach { print($0)}
//luckyNumbers.filter { $0 % 2 != 0 }.sort().map { "\($0) is lucky" }.forEach { print($0)}
// Error "Value of tuple type '()' has no member 'map'"
Источник: Stack Overflow на русском