gistfile1.js

function bind2(fun, obj) {
  return function() {
    fun.call(obj);
  };
}

function displayName() {
  console.log(this.name);
}

var obj1 = {name: "Deepak"};
var obj2 = {name: "Chetan"};

var displayName = bind2(displayName, obj1);

displayName();                 // "Deepak"
displayName.call(obj2);        // "Deepak"