Is JavaScript 's "new" Keyword Considered Harmful?

Posted by Pablo Fernandez on Stack Overflow See other posts from Stack Overflow or by Pablo Fernandez
Published on 2008-12-20T15:20:07Z Indexed on 2010/03/19 3:41 UTC
Read the original article Hit count: 432

Filed under:

JavaScript

|

best-practices

In another question, a user pointed out that the new keyword was dangerous to use and proposed a solution to object creation that did not use new... I didn't believe that was true, mostly because I've used Prototype, Scriptaculous and other excellent JavaScript libraries, and everyone of them used the new keyword...

In spite of that, yesterday I was watching Douglas Crockford's talk at YUI theater and he said the exactly same thing, that he didn't use the new keyword anymore in his code.

Is it 'bad' to use the new keyword? what are the advantages and disadvantages of using it?

© Stack Overflow 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 best-practices

Batch Best Practices and Technical Best Practices Updated

as seen on Oracle Blogs - Search for 'Oracle Blogs'
The Batch Best Practices for Oracle Utilities Application Framework based products (Doc Id: 836362.1) and Technical Best Practices for Oracle Utilities Application Framework Based Products (Doc Id: 560367.1) have been updated with updated and new advice for the various versions of the Oracle… >>> More
Partial template specialization of free functions - best practices

as seen on Stack Overflow - Search for 'Stack Overflow'
As most C++ programmers should know, partial template specialization of free functions is disallowed. For example, the following is illegal C++: template <class T, int N> T mul(const T& x) { return x * N; } template <class T> T mul<T, 0>(const T& x) { return T(0); } //… >>> More
Object Oriented PHP Best Practices

as seen on Stack Overflow - Search for 'Stack Overflow'
Say I have a class which represents a person, a variable within that class would be $name. Previously, In my scripts I would create an instance of the object then set the name by just using: $object->name = "x"; However, I was told this was not best practice? That I should have a function set_name()… >>> More
Good place to look for example Database Designs - Best practices

as seen on Stack Overflow - Search for 'Stack Overflow'
I have been given the task to design a database to store a lot of information for our company. Because the task is rather big and contains multiple modules where users should be able to do stuff, I'm worried about designing a good data model for this. I just don't want to end up with a badly designed… >>> More
Notification Email Best Practices--From Server Setup to Programming

as seen on Stack Overflow - Search for 'Stack Overflow'
All, I'm in the process now of building a SaaS tool that allows network admins to generate notification emails to the members of the end-users of our platform (among many many other things). I'm running into a bit of an "out of my expertise" wall, as I know there are a lot of variables involved… >>> More