Towry Wang towry

Lifetime explained

fn main() {
    let x = "hi";   // lifetime a.
    let e;       // e should have a lifetime a.

    {
        let y = "you";   // lifetime b.
        e = check(&x, &y); // here we returned lifetime b.

Testable JavaScript Resources

Testing JavaScript isn't just a thing you can read about in children's fairy tales.

This is just a scratch pad of everything I find. As the really good resources start to float to the top, I'll transition them to a more permanent GitHub repo.

General

Test-Driven JavaScript Development [book]
JavaScript Testing Recipes [book]

	#ack is a tool like grep, designed for programmers with large trees of heterogeneous source code

	#to install ack, see http://betterthangrep.com/
	#to use ack, launch terminal (mac osx) and type 'ack <some_keywords>'
	#ack will search all files in the current directory & sub-directories

	#here's how I have my config file setup. this file is located on mac osx here
	# ~/.ackrc

	# Always sort the files

 require_relative "customer"
 require_relative "user"
 # context bind role to object.
 # by using the extend method in ruby.
 # now the data object has some behaviors that get from the role class(Customer).
 class Context
   def initialize(user, book)
     @customer, @book = user, book
     @customer.extend(Customer)

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

	import AppKit

	let dateFormatter = DateFormatter()
	dateFormatter.dateStyle = .long
	dateFormatter.timeStyle = .none

	let dateStr = "2017-10-12"

	mr Marathi
	bs Bosnian
	ee_TG Ewe (Togo)
	ms Malay
	kam_KE Kamba (Kenya)
	mt Maltese
	ha Hausa
	es_HN Spanish (Honduras)
	ml_IN Malayalam (India)
	ro_MD Romanian (Moldova)

	//
	// https://medium.com/@jegnux/safe-collection-subsripting-in-swift-3771f16f883
	// https://github.com/ReactiveX/RxSwift/issues/826
	//


	import Foundation

	// we define a fire protocol.
	protocol FireProtocol {

	import PlaygroundSupport

	public func playgroundShouldContinueIndefinitely() {
	PlaygroundPage.current.needsInfiniteExecution = true
	}

	// So associated objects just store object in anoter place, use property to
	// associate the object with the class object.

	import Foundation

	let data: Data?
	var dataKey: Void?

	data = Data(count: 10)
	data?.insert(9, at: 0)

	/// https://github.com/apple/swift-evolution/blob/master/proposals/0142-associated-types-constraints.md

	protocol SubContainer: Container {
	associatedtype Item: Equatable
	}

	protocol Container {
	associatedtype Item
	// error: 'where' clause cannot be attached to an associated type declaration
	// error: type may not reference itself as a requirement