nicar-js.js

// Types
var one = 1;
var two = 2;
three;
window.three;
window.one = 1;
one = 1;
var one = [];
var one = {one: 1};
one.two = 1;

[] + {};
{} + [];

"1" + null;

undefined = true;

"1" == 1;
"1" === 1;

Math.sqrt(-1);
Math.sqrt(-1) === Math.sqrt(-1);

// functions
var fn = function(){ console.log(this.name); };
window.name = 'jeff!';
fn();

// semicolons
var newFn = function(){
  return
    'Why hi there!';
};

newFn();

// this
var a = {name: 'a'};
var b = {name: 'b'};

fn.call(a);
fn.call(b);

// arguments
(function iffe(){
  console.log(arguments);
  console.log(arguments.callee);
  console.log(arguments.caller); // deprecated
  console.log(arguments.length);
  console.log(arguments.__proto__); // not array [];
})(one, two);

['one', 'two', 'three'].slice();

// controlling this and partial application
var bind = function(fn, self){
  return function(){
    var args = [].slice.call(arguments);
    return fn.apply(self, args)
  };
};

var bound = bind(a, fn);
bound.call(b);

// prototypes
a.hasOwnProperty('name');
a.__proto__;

var MyClass = function(){
  this.newName = 'Oh NO!';
  console.log(this);
};

MyClass();
console.log(newName);

var c = new MyClass();

MyClass.prototype.hello = function(){
  console.log('HELLO NICAR!');
};
c.hello();

MyClass.prototype.hello = function(){
  console.log('BYE!');
};
c.hello();

c.__proto__;

// inheritance in javascript
super // <- oh no
var inherits = function(parent, child) {
  var ctor = function(){};
  ctor.prototype = parent.prototype;
  child._super = parent.prototype;
  child.prototype = new ctor();
  child.prototype.constructor = child;
};

var Other = function(){
  MyClass.call(this);
};
inherits(MyClass, Other);

var o = new Other();
o.hello();
Other.prototype.hasOwnProperty('hello');
Other.prototype.hello;
Other.prototype.__proto__.hasOwnProperty('hello');

Other.prototype.__proto__;
Other.prototype.__proto__.constructor;

// Ok, now for the main event, writing evented code!

var extend = function(obj){
  var args = [].slice.call(arguments);

  for(var i = 0; i < args.length; i++)
    for(var j in args[i])
      obj[j] = args[i][j];

  return obj;
};

extend({}, {name: 'hello!'}, {tag: '#NICAR'});


var events = {
  on : function(ev, fn){
    this._callbacks = this._callbacks || {};
    this._callbacks[ev] = this._callbacks[ev] || [];
    this._callbacks[ev].push(fn);
  }
};

events.off = function(ev, fn){
  if(!this._callbacks[ev]) return;
  var cbs = this._callbacks[ev], args = [].slice.call(arguments);
  for(var i = 0; i < cbs.length; i++)
    if(cb === fn) cbs.slice(1, i);
};

events.trigger = function(ev) {
  if(!this._callbacks[ev]) return;
  var cbs = this._callbacks[ev], args = [].slice.call(arguments);

  for(var i = 0; i < cbs.length; i++)
    cbs[i].apply(this, args);
};


var Publisher = function(){
  this.hello = 'yeah';
  this.on('hello', function() { console.log(this.hello); });
};
extend(Publisher.prototype, events);

var a = new Publisher();

var Listener = function(){
  a.on('hello', function(){ console.log('heyo!'); });
};
var l = new Listener();
a._callbacks
a.trigger('hello');