Using reduce to convert an array to a dictionary in Swift

Reduce.swift

let playersArray: [[String: String]] = [
    ["number": "1", "name": "De Gea", "position": "G"],
    ["number": "3", "name": "Bailly", "position": "D"],
    ["number": "6", "name": "Pogba", "position": "M"],
    ["number": "9", "name": "Ibrahimovic", "position": "F"],
    ["number": "8", "name": "Mata", "position": "M"],
    ["number": "10", "name": "Rooney", "position": "F"]
]

let playersDictionary = playersArray.reduce([String:[String:String]](), { (dict, tuple) in
    guard let number = tuple["number"] else { return dict }
    var dict = dict
    dict[number] = tuple
    return dict
})

// [
//    "9": ["position": "F", "number": "9", "name": "Ibrahimovic"], 
//    "1": ["position": "G", "number": "1", "name": "De Gea"], 
//    "8": ["position": "M", "number": "8", "name": "Mata"], 
//    "10": ["position": "F", "number": "10", "name": "Rooney"], 
//    "6": ["position": "M", "number": "6", "name": "Pogba"], 
//    "3": ["position": "D", "number": "3", "name": "Bailly"]
// ]