selfish.js

/* vim:set ts=2 sw=2 sts=2 expandtab */
/*jshint undef: true es5: true node: true devel: true evil: true
         forin: true latedef: false supernew: true */
/*global define: true */

(typeof define !== "function" ? function($){ $(null, typeof exports !== 'undefined' ? exports : window); } : define)(function(require, exports) {

"use strict";

exports.Base = Object.freeze(Object.create(Object.prototype, {
  /**
   * Property representing a base prototype, object `this` prototype extends.
   * If `this` object is an object created by `.new`, then `base` will be
   * a prototype that, prototype of this extends. This property is intended to
   * for calling methods of base / super prototype with out directly reference.
   * @examples
   *
   *    var Point = Base.extend({
   *      initialize: function Point(x, y) {
   *        point.x = x || 0;
   *        point.y = y || 0;
   *      },
   *      toString: function toString() {
   *        return this.x + ':' + this.y
   *      }
   *    });
   */
  base: { value: Object.prototype },
  /**
   * Creates an object that inherits from `this` object (Analog of
   * `new Object()`).
   * @examples
   *
   *    var Dog = Base.extend({
   *      bark: function bark() {
   *        return 'Ruff! Ruff!'
   *      }
   *    });
   *    var dog = Dog.new();
   */
  'new': { value: function () {
    var object = Object.create(this);
    object.initialize.apply(object, arguments);
    return object;
  }},
  initialize: { value: function Base() {
  }},
  /**
   * Takes any number of argument objects and returns frozen, composite object
   * that inherits from `this` object and combines all of the own properties of
   * the argument objects. (Objects returned by this function are frozen as
   * they are intended to be used as types).
   *
   * If two or more argument objects have own properties with the same name,
   * the property is overridden, with precedence from right to left, implying,
   * that properties of the object on the left are overridden by a same named
   * property of the object on the right.
   * @examples
   *
   *    // ## Object composition ##
   *
   *    var HEX = Base.extend({
   *      hex: function hex() {
   *        return '#' + this.color;
   *      }
   *    })
   *
   *    var RGB = Base.extend({
   *      red: function red() {
   *        return parseInt(this.color.substr(0, 2), 16);
   *      },
   *      green: function green() {
   *        return parseInt(this.color.substr(2, 2), 16);
   *      },
   *      blue: function blue() {
   *        return parseInt(this.color.substr(4, 2), 16);
   *      }
   *    })
   *
   *    var CMYK = Base.extend(RGB, {
   *      black: function black() {
   *        var color = Math.max(Math.max(this.red(), this.green()), this.blue());
   *        return (1 - color / 255).toFixed(4);
   *      },
   *      cyan: function cyan() {
   *        var K = this.black();
   *        return (((1 - this.red() / 255).toFixed(4) - K) / (1 - K)).toFixed(4);
   *      },
   *      magenta: function magenta() {
   *        var K = this.black();
   *        return (((1 - this.green() / 255).toFixed(4) - K) / (1 - K)).toFixed(4);
   *      },
   *      yellow: function yellow() {
   *        var K = this.black();
   *        return (((1 - this.blue() / 255).toFixed(4) - K) / (1 - K)).toFixed(4);
   *      }
   *    })
   *
   *    var Color = Base.extend(HEX, RGB, CMYK, {
   *      initialize: function Color(color) {
   *        this.color = color;
   *      }
   *    });
   *
   *    // ## Prototypal inheritance ##
   *
   *    var Pixel = Color.extend({
   *      initialize: function Pixel(x, y, hex) {
   *        this.base.initialize.call(this, hex);
   *        this.x = x;
   *        this.y = y;
   *      },
   *      toString: function toString() {
   *        return this.x + ':' + this.y + '@' + this.hex();
   *      }
   *    });
   *
   *    var pixel = Pixel.new(11, 23, 'CC3399')
   *    pixel.toString(); // 11:23@#CC3399
   *
   *    pixel.red();      // 204
   *    pixel.green();    // 51
   *    pixel.blue();     // 153
   *
   *    pixel.cyan();     // 0.0000
   *    pixel.magenta();  // 0.7500
   *    pixel.yellow();   // 0.2500
   *
   */
  extend: { value: function extend() {
    // Defining an ES5 property descriptor map, where own property
    // descriptors of all given objects are copied.
    var descriptor = {};
    Array.prototype.forEach.call(arguments, function (properties) {
      Object.getOwnPropertyNames(properties).forEach(function(name) {
        descriptor[name] = Object.getOwnPropertyDescriptor(properties, name);
      });
    });
    // In addition `base` property is defined that points to a primary ancestor
    // of the resulting object.
    descriptor.base = { value: this };
    return Object.freeze(Object.create(this, descriptor));
  }}
}));

});