Prototypical Inheritance with Object.create

type.js

function type(prototype, members, properties, objectMembers) {
  var exports = {}, key;

  properties = properties || {};
  objectMembers = objectMembers || {};

  exports.prototype = Object.create(prototype || {}, properties);
  
  for ( key in members ) {
    exports.prototype[key] = members[key];
  }
  
  if ( !exports.prototype.init ) {
    exports.prototype.init = function() {};
  }
  
  for ( key in objectMembers ) {
    exports[key] = objectMembers[key];
  }
  
  if ( !exports.create ) {
    exports.create = function() {
      var o = Object.create(exports.prototype);
      o.init.apply(o, arguments);
      return o;
    };
  }
  
  return exports;
}

usage.js

var Bounds = type(
  // empty prototype, no parent
  {},
  
  {
    init: function( x, y, w, h ) {
      this.x = x;
      this.y = y;
      this.width = w;
      this.height = h;
  }
);