So this IE9-requires-Win7 business isn’t more of the same? Firefox 4, Chrome 10, Opera 10, etc. don’t seem to need the features in Win7. A browser is supposed to be an APPLICATION not an extension of the OS.

I believe it’s another way to try to overcome their Vista debacle and get their OS sales numbers back up. (Read how Ballmer is remaking Microsoft and lots of long-time high-level managers are out, including Ray Ozzie, in the trade press.) They’re becoming (more of) a cash-generating machine at the expense of customer satisfaction (so what else is new).

Chuck Somerville
Eastman Kodak Company (still on XP)
Dayton Ohio

Another good reason to use 10ms is you can then preempt your regular timeouts using a timeout of 0ms.

Lastly, if you have access to different operating systems, it might be interesting to compare same browsers on different OSs. Since the timeout uses the OS time, then the result.

Just some food for thought.

Thanks for your enthusiastic comment.

I think your idea with a “newClass” prefix is really great. It gives the compromised solution for our last discussion with Andreas Grech. It starts with small letter and it gives precise indication of the Class. Really nice.

Talking about performance warning, you are completely right. I will add it as the footnote to the article, together with advices of “new” prefix.

This is an excellent article explaining the pros of the factory pattern to simulate “classes”. I just have a couple notes.

First, if you do ever mix constructor functions with factory functions, then you can prefix your factory function names with new. For example, let’s assume I have two “classes” Person and Shape. Person is implemented using a constructor and Shape is implemented using a factory.

function Person(…) {…}
Person.prototype.foo = …

function newShape(…) {
return …
}

Then when you’re using them, it will be either “new Person()” or “newShape()”

Secondly, I am a huge personal fan of the factory style for creating objects, but it’s unfair to promote it without warning people of the performance costs. Each and every instance has it’s own copy of every function and a closure for each. This comes as a huge cost if you’re going to be making lots of these.

Anyway, overall a great article.

I think your first paragraph is exactly the place where our thoughts are going separate ways. The fundamental difference in views, at which we ground our arguments, pros and cons.

As I said, my main idea is that choosing only one factory and using the same conventions everywhere for the whole codebase is just a “MUST”. It shouldn’t matter “if there is more than developer working on the same library”. This is the reasons why I do not see “an uncommon sight to see ‘var p = new Person();’ and ‘var u = user();’” in the code. Having such mixin in your code, means that conventions are not used. And if such developers unable to stick to one format in their own code, how do you want them to stick to the global well-known conventions for the whole JavaScript?

Of course, you are totally right that we should stick to the common and well-known conventions, personally I think that too. The only reason I used PascalCase naming is to make the clear separation between Classes and function calls. In the case when more than one library is used, indeed, it might be better to use lowercase names for factory classes.