The immediate function executes as soon as it is defined. To understand the role of immediate function, let’s see the difference between a function and an immediate function −
Here’s immediate function −
(function() { var str = "display"; }()); function display() { // this returns undefined alert(str); }
Here’s a function −
var str = "display"; function display() { // This returns "display" alert(str); }
Let’s see another example of immediate functions −
var name = 'Amit'; (function(sName) { alert( 'Student name = ' + sName ); }(sName))