CustomTypeLiterals.swift

import UIKit

struct Person: ExpressibleByStringLiteral {
    typealias StringLiteralType = String
    init(stringLiteral value: StringLiteralType) {
        let components = value.components(separatedBy: .whitespaces)
        firstName = components[0]
        lastName = components[1]
    }
    let firstName: String
    let lastName: String
}

let person: Person = "Khurram Shehzad"


struct Temperature: ExpressibleByIntegerLiteral {
    typealias IntegerLiteralType = Int
    init(integerLiteral value: Int) {
        t = value
    }
    
    let t: Int
}
func waterBoilingTemperature() -> Temperature {
    return 100
}
let waterBoiling = waterBoilingTemperature()
let waterFreezing: Temperature = 0


class LinkedList: ExpressibleByArrayLiteral {
    var first: Node?
    class Node {
        var value: Int?
        var next: Node?
    }
    typealias ArrayLiteralElement = Int
    required init(arrayLiteral elements: Int...) {
        var current: Node?
        for element in elements {
            if first == nil {
                first = Node()
                first?.value = element
                current = first
            } else {
                let node = Node()
                node.value = element
                current?.next = node
                current = node
            }
        }
    }
}

let linkedList: LinkedList = [1, 2, 3, 4, 5]

struct SolarSystem {
    struct Planet {
        let name: String
        let moonsCount: Int
    }
    let planets: [Planet]
}

extension SolarSystem: ExpressibleByDictionaryLiteral {
    typealias Key = String
    
    typealias Value = Int
    init(dictionaryLiteral elements: (String, Int)...) {
        var planets = [Planet]()
        for element in elements {
            planets.append(Planet(name: element.0, moonsCount: element.1))
        }
        self.planets = planets
    }
}

let ourSolarSystem: SolarSystem = [
    "Mercury": 0,
    "Venus": 0,
    "Earth": 1,
    "Mars": 2,
    "Jupiter": 79,
    "Saturn": 82,
    "Uranus": 27,
    "Neptune": 14]