memberwise init with custom init

memberwise2.swift

// No memberwise initializer
struct Player {
    let name: String
    var score: Int = 0
    init(json: [String: AnyObject]) {

    }
}

// you have the both initializers:
struct Player {
    let name: String
    var score: Int = 0
}

extension Player {
    init(json: [String: AnyObject]) {

    }
}