Re: CSS2.1 :lang

> With regards to HTML, the current text mentions META, but I think
> this should be removed. The META http-equivalent was designed to
> generate HTTP headers, but has never been used that way. The only

I'm not convinced that META was designed.  It's simple use seems to
be better handled, in many cases, by link; I think it was just there
to allow non-hyperlinked meta data from word processors to be dumped
into their HTML exports.  For http-equiv, although you can make a case
in terms of non-HTTP delivered documents, I think its really there
for single technology users, who want everything as "HTML".[1]

> place that I know it is used these days is for 'charset'.

It is often used, purportedly to control caches, and some versions
of the HTML specification mention this (may just be draft versions).
In this context, it is usually used as "Pragma: no-cache"[2], which my
reading of the  HTTP 1.1 specification says is only allowed server to
client, and only for legacy purposes, and is, as content, normally
ignored by shared caches.

It's also used for Refresh, although that is a proprietory standard,
and the most common use, with a delay of zero, is mentioned in the
HTML specification as a SHOULD NOT.  Refresh does work as a real HTTP
header on the big two browser brands and thus can be used for non-HTML
documents, e.g. unframed web cam images.

I've also seen it used for languages, although you have to have a well
above average understanding of the web to be doing that, or your authoring
tool does it and, most likely, puts in an inappropriate default.

So, while I think that META is not one of the best things that happened
to HTML, it is something that has to be allowed for.

[1] where the popular definition of HTML is the combination of:
- EcmaScript
- IE Document Object Model
- IE Browser Object Model
- Flash

Flash does rather break the single technology model, but, because
CSS and scripting are in the same file, they are seen as a single 
technology, with HTML.

[2] Most of HTTP 1.1 is about efficient caching, but what is the first
thing that designers ask:  how do you disable caching?

Received on Saturday, 18 October 2003 06:47:56 UTC