`_` にマッチするよね… #swift #CodePiece

CodePiece.swift

switch "" as Optional {
case _:
    print("_")
case _?:  // ⚠️ Case will never be executed
    print("_?")
//case _??: // ❗️error: '?' pattern cannot match values of type 'String'
//    print("_??")
default:
    print("s")
}