No, IIFE doesn’t execute the code in document ready. 1. Just in IIFE: (function($) { console.log(‘logs immediately’); })(jQuery); This code runs immediately logs “logs immediately” without document is ready. 2. Within ready: (function($) { $(document).ready(function(){ console.log(‘logs after ready’); }); })(jQuery); Runs the code immediately and waits for document ready and logs “logs after ready”. This … Read more
This is a concise way to form an immediately executed function expression. Traditionally, people have used these two forms (function(){ }()); // Recommended by Crockford (function(){ })(); // What most people use If you try to just use function(){ }(); // Syntax error it will be a syntax error, because it is interpreted as a … Read more
The first uses jQuery to bind a function to the document.ready event. The second declares and immediately executes a function.
In all cases you are doing an anonymous function. I think 1 is the same as 2. In the third case you are passing jQuery as an argument. This is done when you want to encapsulate jQuery within your function’s scope. For instance, in your application, jQuery var could be jQuery. But within your anonymous … Read more
The pattern is called self-invocation, a self-invoking function. It can create a closure, but that is an effect of the pattern (perhaps the intended effect), not the pattern itself.
You can try: (window.powers = function(i) { /*Code here*/ alert(‘test : ‘ + i); })(2); <a href=”#” onclick=”powers(654)”>Click</a> Working link : http://jsfiddle.net/SqBp8/ It gets called on load, and I have added it to an anchor tag to change the parameter and alert.
With the increasing popularity of JavaScript frameworks, the $ sign was used in many different occasions. So, to alleviate possible clashes, you can use those constructs: (function ($){ // Your code using $ here. })(jQuery); Specifically, that’s an anonymous function declaration which gets executed immediately passing the main jQuery object as parameter. Inside that function, … Read more
These two different techniques have a functional difference as well as a difference in appearance. The potential advantages of one technique over the other will be due to these differences. Concision Javascript is a language where concision can be very important, because Javascript is downloaded when the page loads. That means that the more concise … Read more
Your assumptions are almost correct. Let’s review those first. It assigns the return of a self-executing function This is called an Immediately-invoked function expression or IIFE It defines a local variable within this function This is the way of having private object fields in JavaScript as it does not provide the private keyword or functionality … Read more
From Douglass Crockford’s style convention guide: (search for “invoked immediately”) When a function is to be invoked immediately, the entire invocation expression should be wrapped in parens so that it is clear that the value being produced is the result of the function and not the function itself. So, basically, he feels it makes more … Read more