Emoji Sums

emojisums.swift

struct Emoji {
    var character: String
}

let emojiSums = [
    "😐": ["😊", "😒"],
    "😀": ["😊", "😊"],
    "😭": ["😒", "😒"],
    "🍖": ["🐔", "🔥"]
    ].map({(sum: $0, parts: $1.sorted())})

func + (left: Emoji, right: Emoji) -> Emoji {

    let characters = [left.character, right.character].sorted()
    
    for (sum, parts) in emojiSums {
        if parts == characters {
            return Emoji(character: sum)
        }
    }
    return "😵"
}

extension Emoji: StringLiteralConvertible, CustomStringConvertible {

    var description: String {
        get {
            return character
        }
    }

    init(stringLiteral value: String) {
        self.character = value
    }
    
    init(extendedGraphemeClusterLiteral value: String) {
        self.character = value
    }
    
    init(unicodeScalarLiteral value: String) {
        self.character = value
    }
}

let happy:Emoji = "😊"
let sad:Emoji = "😒"
let chicken:Emoji = "🐔"
let fire:Emoji = "🔥"

print(happy + sad)
print(happy + happy)
print(sad + sad)
print(chicken + fire)