使用开关满足多个约束之一

Created: November-22, 2018

你可以创建一个元组并使用如下所示的开关：

var str: String? = "hi"
var x: Int? = 5

switch (str, x) {
case (.Some,.Some):
    print("Both have values")
case (.Some, nil):
    print("String has a value")
case (nil, .Some):
    print("Int has a value")
case (nil, nil):
    print("Neither have values")
}