Object.create vs Crockford vs Constructor vs Resig Simple JS Inheritance

JavaScript performance comparison

Revision 42 of this test case created by frooble

Preparation code

<script>
  var sharedPrototype = {
    one: function() {
     return 1;
    },
    two: function() {
     return 2;
    },
    three: function() {
      return 3;
    }
  };
 
  var crockfordCreate = function(proto) {
    var f = function() {};
    f.prototype = proto;
    return new f();
  };
 
  var crockfordEvolved = function (o) {
    function F() {}
    F.prototype = o;
    return new F();
  };

  var Constructor = function() {};
  Constructor.prototype = sharedPrototype;
</script>
<script type="text/javascript">
  /* Simple JavaScript Inheritance
 * By John Resig http://ejohn.org/
 * MIT Licensed.
 */

  // Inspired by base2 and Prototype
  (function() {
    var a = false,
        b = /xyz/.test(function() {
        xyz
      }) ? /\b_super\b/ : /.*/;
    this.Class = function() {};
    Class.extend = function(g) {
      var f = this.prototype;
      a = true;
      var e = new this();
      a = false;
      for (var d in g) {
        e[d] = typeof g[d] == "function" && typeof f[d] == "function" && b.test(g[d]) ? (function(h, i) {
          return function() {
            var k = this._super;
            this._super = f[h];
            var j = i.apply(this, arguments);
            this._super = k;
            return j
          }
        })(d, g[d]) : g[d]
      }
      function c() {
        if (!a && this.init) {
          this.init.apply(this, arguments)
        }
      }
      c.prototype = e;
      c.prototype.constructor = c;
      c.extend = arguments.callee;
      return c
    }
  })();

ResigsClass = Class.extend(sharedPrototype );
</script>

Preparation code output

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Testing in unknown unknown
Test Ops/sec
Object.create()
var i = 100;
while (i--) Object.create(sharedPrototype);
pending…
Crockford Create
var i = 100;
while (i--) crockfordCreate(sharedPrototype);
pending…
Constructor
var i = 100;
var s;
while (i--) s = new Constructor;
pending…
Evolved
var i = 100;
while (i--) crockfordEvolved(sharedPrototype);
pending…
Resig
var i = 100;
var rs ;
while (i--) rs = new ResigsClass();
pending…

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