Array reduce to Dictionary helper function

reduceDictionary.swift

// Definition
extension Array {
    func reduceDictionary<Key: Hashable, Value>(extractKeyValue: Element -> (Key, Value)) -> [Key: Value] {
        return reduce([Key: Value]()) {
            var dictionary = $0.0
            let (key, value) = extractKeyValue($0.1)
            dictionary[key] = value
            return dictionary
        }
    }
}

// How to use
let xs = [
    Dog(id: "001", name: "pochi"),
    Dog(id: "002", name: "jhon"),
    Dog(id: "003", name: "mike"),
]

xs.reduceDictionary{ ($0.id, $0.name) } // => ["001": "pochi", "002": "jhon", "003": "mike"]