What's so useful about closures (in JS)?

Posted by Mark Bubel on Programmers See other posts from Programmers or by Mark Bubel
Published on 2013-07-03T03:23:29Z Indexed on 2013/07/03 5:18 UTC
Read the original article Hit count: 163

Filed under:

JavaScript

|

closures

In my quest to understand closures in the context of JS, I find myself asking why do you even need to use closures? What's so great about having an inner function be able to access the parent function's variables even after the parent function returns? I'm not even sure I asked that question correctly because I don't understand how to use them.

Can someone give a real world example in JS where a closure is more beneficial vs. the alternative, whatever that may be?

© Programmers or respective owner

Related posts about JavaScript

CHAT ROOMs 7 by 6

as seen on Stack Overflow - Search for 'Stack Overflow'
I am looking for chatroom on one page with 7 loggedin users and 6+rows for say 42 users.these users will keep on adding wthnew users.Need urgent help.A PRETTY UNUSUAL Q FOR MOST OF U.What is MORE REQ new features: Usernames are unique to users currently chatting You can see a "currently chatting"… >>> More
Integrating JavaScript Unit Tests with Visual Studio

as seen on Stephen Walter - Search for 'Stephen Walter'
Modern ASP.NET web applications take full advantage of client-side JavaScript to provide better interactivity and responsiveness. If you are building an ASP.NET application in the right way, you quickly end up with lots and lots of JavaScript code. When writing server code, you should be writing… >>> More
Has Javascript developed beyond what it was originally designed to do?

as seen on Programmers - Search for 'Programmers'
I've been talking with a friend about the purpose of Javascript, when and how it should be used, etc. He quoted that: JavaScript was designed to add interactivity to HTML pages [...] JavaScript gives HTML designers a programming tool HTML authors are normally not programmers… >>> More
PHP, javascript, single quote problems with IE when passing variable from ajax post to javascript fu

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi! I have been trying to get this to work for a while, and I suspect there's an easy solution that I just can't find. My head feels like jelly and I would really appreciate any help. My main page.php makes a .post() to backend.php and fetches a list of cities which it echoes in the form of: <li… >>> More
Javascript in XSL that is loaded by Javascript

as seen on Stack Overflow - Search for 'Stack Overflow'
Is there anyway to have javascript run when a XSL sheet has been applied to an XML file by Javascript? I am using a JQuery plugin to apply the sheet to the xml but the javascript that is located inside of the XSL file will not run. I put the Javascript at the bottom of the file and it still does… >>> More

Related posts about closures

what are the benefits of closure, primarily for PHP?

as seen on Programmers - Search for 'Programmers'
I am beginning the process of moving code over to PHP 5.3 and one of the most highly touted features of PHP 5.3 is the ability to use closures. My understanding of closures is that they allow anonymous functions, can be assigned to variable names, and have interesting scoping abilities. From my… >>> More
Does Java need closures?

as seen on Stack Overflow - Search for 'Stack Overflow'
I've been reading a lot lately about the next release of Java possibly supporting closures. I feel like I have a pretty firm grasp on what closures are, but I can't think of a solid example of how they would make an Object-Oriented language "better". Can anyone give me a specific use-case where… >>> More
How to emulate closures in c

as seen on Stack Overflow - Search for 'Stack Overflow'
Is there a simple way? >>> More
C# - closures over class fields inside an initializer?

as seen on Stack Overflow - Search for 'Stack Overflow'
Consider the following code: using System; namespace ConsoleApplication2 { class Program { static void Main(string[] args) { var square = new Square(4); Console.WriteLine(square.Calculate()); } } class MathOp { … >>> More
Python serialize lexical closures?

as seen on Stack Overflow - Search for 'Stack Overflow'
Is there a way to serialize a lexical closure in Python using the standard library? pickle and marshal appear not to work with lexical closures. I don't really care about the details of binary vs. string serialization, etc., it just has to work. For example: def foo(bar, baz) : def closure(waldo)… >>> More