Using pattern matching on tuples of Optionals

Testing optionals

// Playground - noun: a place where people can play

import Cocoa

func checkOptionals(a:Dictionary<String,Int>,key1:String,key2:String) {
    switch (a[key1],a[key2]) {
        case (.Some(_),.Some(_)): println("both")
        case (.Some(let a),.None): println("first " + String(a))
        case (.None,.Some(let b)): println("second " + String(b))
        default: println("neither")
    }
}

let dict = ["x":5,"y":6,"z":7]

checkOptionals(dict,"g","h")
checkOptionals(dict,"x","g")
checkOptionals(dict,"h","y")
checkOptionals(dict,"x","z")

Console output is:

    neither
    first 5
    second 6
    both