Tuesday, September 18, 2007

noscript tag behaviour and head conflicts

In this Web 2.something era there's a big problem with noscript tag and I wonder what does W3 think about them.

noscript and its standard implementation

This tag is really useful to increase page informations or accessibility, allowing developers to show an alternative content if user has not JavaScript enabled or his browser doesn't support other kind of tags.

<script type="text/jvascript">doStuff()</script>
<noscript>Your browser can't do my Stuff</noscript>

This is a basic example of noscript usage and expected behaviour is that every JS compatible browser will try to execute code insde script tag while every JS disabled or not compatible browser will show an alternative information.

So, what's wrong with noscript ?

When a browser is JS compatible ignores totally noscript tag.
It doesn't render its informations, just "jump" after the end of this tag.
At the same time, if a browser is not compatible with tag used before noscript, it will ignore totally every kind of its informations such src, code execution plugin initializzation or other things.

In few words, noscript is a WAI-AAA but at the same time has too many limitations that are totally against the real accessibility.

In fact, (X)HTML doesn't accept a noscript tag inside head one and at the same time doesn't accept external resources inside noscript tag.

This simply means that You can't include a dedicated stylesheet or link tag inside noscript one so every navigator need to download entire page, included noscript, even if it'll never use its informations.

At the same time is not possible to run a UI dedicated style using JavaScript inside head tag, the right place to put style, link and / or script tags.

All these things mean that a page can't separe, respecting W3 standards, content for JS enabled browsers and other, simply because every navigator has to download at least two kinds of CSS, even if the biggest one, dedicated for example to render correctly YUI!, Dojo, Ext, Interface, Moo or every other client libraries that today are strongly used inside a big range of sites.

I'm obviously talking about external resources and DOM with a goal to make page smaller than ever downloading only useful resources: JS + dedicated CSS for enabled browsers, dedicated CSS for browsers without JS support.

I read about new XHTML 2.0 handler tag, but the question, now, is:
will W3 ever remove from its validator program the error about noscript inside head tag?

Can anyone explain me why noscript can't be after a script inside head and why noscript can't contain in every part of page an external resource?

Please, tell me if there's a way to solve this problem or if ignore them is the only one solution just because every browser support noscript tag inside head one and load its external resources correctly, thank You.

<script type="text/javascript"><!--//
// this file should be download only by JS enabled browsers
var link = document.createElement("link");
link.rel = "stylesheet";
link.media = "screen";
link.href = "myBigLibrary.css";
title="more speed for everyone"

No comments:

Post a Comment