使用開關滿足多個約束之一

你可以建立一個元組並使用如下所示的開關：

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")
}