"Everyone should be upset with JavaScript"

--Eirik http://github.com/clux

JS

DOM + AJAX APIs

Canvas, WebGL, Websockets, Webworkers, Web components

NodeJS

CoffeeScript, TypeScript, ASM.js

Core language ->

Core language

operators, syntax, keywords, inheritance

timers

scope and closures

original 8 built in types

Prototypes

function User(name) {
  this.name = name;
}
User.locate = function (name) { .. };
User.prototype.greet = function () { return 'hi: ' + this.name; }


var me = new User('Eirik');
me instanceof User; // true








// where does properties on `me` live?
// NB: me.property === me['property']


// me.qwfp
// User.prototype.qwfp
// Object.prototype.qwfp
// -> undefined

Object

{key: value, ...}

Array

[a, b, c]

String

"ab©"

Date

new Date()

Boolean

true,false

Number

123

RegExp

/^match[u|i]$/

Function

function (args) { body; }

Call/Apply/Bind

var fn = function () { code(); }
// all equivalent
fn(arg1, arg2, arg3);
fn.call(this, arg1, arg2, arg3);
fn.apply(this, [arg1, arg2, arg3]);
fn.bind(this, arg1, arg2, arg3)();
fn.bind(this, arg1, arg2)(arg3);
fn.bind(this, arg1)(arg2, arg3);
fn.bind(this)(arg1, arg2, arg3);

this

function User(name) {
	this.name = name;
}

for (var i = 0; i < 5; i += 1) ;
console.log(i) // 5




















User.prototype.context = function () {
	return this;
};
var ea = new User('eirik');
ea.context(); // { name: 'eirik' }
this; // global object

User.prototype.context = function () {
	return (function () {
		return this;
	})();
};
ea.context(); // global object




User.prototype.context = function () {
	return (function () {
		return this;
	}).call(this);
};
ea.context(); // { name: 'eirik' }



User.prototype.context = function () {
	var that = this;
	return (function () {
	  return that;
	})();
};

poe.js