Delegate

// used to fix "this" prob with Function.apply to give call proper scope
// nice method to put in your lib
function delegate(instance, method) {
  return function() {
    return method.apply(instance, arguments);
  }
}
 
function Animal(name) {
  this.name = name;
  this.hello = function() {
    alert("hello " + this.name);
  }
}
 
var dog = new Animal("Jake");
var button = {
  onclick : delegate(dog, dog.hello)
};
button.onclick();