Prototypes

prototypes.js

/* POINT */

function Point(x, y) {
  this.x = x;
  this.y = y;
}

Point.prototype.move = function(deltaX, deltaY) {
  this.x += deltaX;
  this.y += deltaY;
}

Point.prototype.constructor = Point;

/* POINT WITH NAME */

function PointWithName(x, y, name) {
  Point.call(this, x, y);
  this.name = name;
}

PointWithName.prototype = Object.create(Point.prototype);
PointWithName.prototype.construstor = PointWithName;

/* CUSTOM NEW */

function customNew(constr, args) {
  var thisValue = Object.create(constr.prototype);
  constr.apply(thisValue, args);
  return thisValue;
}

/* OBJECT CREATION */

var p = customNew(Point, [1, 2]);
var pWithName = customNew(PointWithName, [1, 2, 'Awesome Point']);

console.log(p);
console.log(pWithName);