Yes, this can be done. When you have a global scope, you can use a variable without declaring it. The following “no var” variable “points” will look at the scope chain, wince var keyword isn’t use −
<html>
<body>
<script>
var rank = 5;
points = 50;
marks = 300;
// Anonymous function
(function() {
points = 100; //overwrites global scope points
var rank = 4; //new rank variable is created in this' function's scope
var marks = 900;
document.write(rank+"\r\n"); //prints 4
document.write(points+"\r\n"); //prints 100
document.write(marks+"\r\n"); //prints 900
})();
document.write('<br/>');
document.write('<br/>');
document.write(rank+"\r\n"); //prints 5
document.write(points+"\r\n"); //prints 100
document.write(marks+"\r\n"); //prints 300
</script>
</body>
</html>