bind.js

Function.prototype.bind = function(that) {
  var args = Array.prototype.slice.call(arguments)
  return function() {
    this.call(that, args)
  }
}


var myobj = {
  name : "blake",
  colors : ["blue", "purple"],
  forEach : function(array, action) {
    for (var i = 0; i < array.length; i++)
      action(array[i]);
  },
  calculate : function() {
    this.forEach(this.colors, (function(e) {console.log(this.name)}).bind(this))
  }

}

myobj.calculate()