yossan

import Foundation

class Value: NSObject {
    @objc let raw: Int
    init(_ raw: Int) {
        self.raw = raw
    }

    override var description: String {
        return "\(self.raw)"

yossan

class List<T> {
    var head: Node<T>?
    var last: Node<T>?

    class Node<T> {
        let value: T
        var next: Node<T>? = nil

        init(_ value: T) {
            self.value = value

yossan

/*
  $ swift --version
  Apple Swift version 4.0.2 (swiftlang-900.0.69.2 clang-900.0.38)
  Target: x86_64-apple-macosx10.9
*/

class Foo {
    // not called!
    deinit {
        print(type(of: self), #function)

yossan

enum Pair<T, WORLD> {
    case cons (T, WORLD) // (value, outside)
}

// Outside　the computer
typealias WORLD = Any

// IO Monad Instance (a.k.a IO Action)
typealias IO<T> = (WORLD) -> Pair<T, WORLD>

yossan

func getTupple() -> (first: Int, secound: Int) {
    return (0, 1)
}

//Gets value with label
let f = getTupple().first
print(f)

yossan

var message: String = "test"
// Returns Array<Character> 
let conv = message.flatMap { (chr) /*Character*/ in
    return String(chr) + "/"
}
print(type(of: conv)) //Array<Character>
print(conv) //["t", "/", "e", "/", "s", "/", "t", "/"] 

//https://developer.apple.com/documentation/swift/string/2903352-flatmap
let conv2 = message.flatMap { (chr) /*Character*/ -> String? in

yossan

/*
 Hanoi Tower
 Calucuating How many moves in Swift
 result is 2^n - 1
 */
func hanoi(_ n: Int, from: String="from", target: String="target", other: String="other") -> Int {
    guard n != 0 else { return 0 }
    // move top of n-1 disks on from to other
    var count = hanoi(n-1, from: from, target: other, other: target)

yossan

import Foundation
do {
struct Token {
    var dict: [String: Any]? = nil
    init(dictionary: [String: Any]) {
        self.dict = dictionary
    }

    func data() -> Data {
        let pointer = UnsafeMutablePointer<Token>.allocate(capacity: 1)

yossan

import Foundation
let str = "✑🍍🍎✒"
// returns little endian
let data = str.withCString(encodedAs: UTF16.self) { (lead) -> Data in
    let ret = UnsafeBufferPointer(start: lead, count: str.utf16.count)
    let data = Data(buffer: ret)
    return data
}

let decode = String(data: data, encoding: .utf16LittleEndian)!

yossan

/// Creating Stream for CountDown
func createCountDown(_ n: Int) -> Array<Any> {
    guard n > 0 else {
        return [0]
    }

    return [n, {
        return createCountDown(n-1)
    }]
}