subscript.swift

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

//Subscript: shortcut for accessing the member elements in a collection, list, or sequence.

import UIKit
//#1
struct TimesTable {
    let multiplier: Int
    subscript(index: Int) -> Int {
        return multiplier * index
    }
}
let threeTimesTable = TimesTable(multiplier: 3)
print("six times three is \(threeTimesTable[6])")


//#2
class Room {
    let name: String
    init(name: String) { self.name = name }
}
class Residence {
    var rooms = [Room]()
    var numberOfRooms: Int {
        return rooms.count
    }
    subscript(i: Int) -> Room {
        get {
            return rooms[i]
        }
        set {
            rooms[i] = newValue
        }
    }
    func printNumberOfRooms() {
        print("The number of rooms is \(numberOfRooms)")
    }
}

let nrrooms = Residence()
nrrooms.rooms = [Room(name: "one"), Room(name: "two")]
nrrooms.printNumberOfRooms()