gistfile1.js

var times = 500000

function bm(label, fn) {
  var start = +new Date
  fn()
  print('  ' + label + ' : ' + (+new Date - start) + ' ms')
}

print('\n  running ' + times + ' times\n')

bm('prototype', function(){
  var n = times
  while (n--) {
    function User(name) {
      this.name = name
    }
    function Admin(name) {
      User.call(this, name)
    }
    new Admin('tj')
  }
})

bm('Object._extends_() 1', function(){
  var n = times
  while (n--) {
    function User(name) {
      this.name = name
    }
    Object._extends_( Admin, User );
    function Admin(name) {
      User.call(this, name)
    }
    new Admin('tj')
  }
})

bm('Object._extends_() 2', function(){
  var n = times
  while (n--) {
    function User(name) {
      this.name = name
    }
    Object._extends_( Admin, User );
    function Admin(name) {
      this.name = name
    }
    new Admin('tj')
  }
})

// --- Instance Creation

print('\n  instance creation \n')

bm('prototype instance', function(){
  var n = times
  function User(name) {
    this.name = name
  }
  function Admin(name) {
    User.call(this, name)
  }
  while (n--) new Admin('tj')
})


bm('Object._extends_() 1', function(){
  var n = times
    function User(name) {
      this.name = name
    }
    Object._extends_( Admin, User );
    function Admin(name) {
      User.call(this, name)
    }
  while (n--) {
    new Admin('tj')
  }
})

var o;
bm('Object._extends_() 2', function(){
  var n = times
    function User(name) {
      this.name = name
    }
    Object._extends_( Admin, User );
    function Admin(name) {
      this.name = name
    }
  while (n--) {
    new Admin('tj')
  }
  o = new Admin('tj');
})

print( print_r( o ) );

print('')