Re: Versioning re-visited (was : mixed signals on "Writing HTML documents", tutorial, etc.)

Philip Taylor (Webmaster) wrote:

> The goalposts are fixed, for perpetuity.  A valid document
> will remain valid, an invalid document will remain invalid,
> and a validator will never give different answers concerning
> a particular instantiation of a document.  Furthermore,
> a user agent can -- <em>if it so chooses</em> -- make use
> of the DOCTYPE in order to vary its parsing, rendering and
> so on.  By providing versioning information in the DOCTYPE,

While I think that having version information in the instance is very
useful, please abandon idea of using DOCTYPE for storing version number.
There are many arguments for not using DOCTYPE, many of them were also
posted on this list. From top of my head these are:

1. DOCTYPE information is not exposed in many XML APIs, you can't access
it in majority of XML tools

2. DOCTYPE is tightly related to DTDs. But version of language and
schema/DTD are two very different things. Today, DTD is legacy schema
language which has many problems compared to the newer schema languages
like RELAX NG or W3C XML Schema.

Storing version information in and attribute or element doesn't have
such problems.

				Jirka

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