Re: [xX][mM][lL] is reserved

Tim Bray (tbray@textuality.com)
Tue, 05 May 1998 11:44:25 -0700


At 10:15 AM 5/5/98 -0700, Chris Lovett wrote:
>Currently MSXML disallows "xml" from being used as a "namespace", for
>example: "xml:foo" since this seems to be the way the XML spec is heading
>with "xml:space" and "xml:lang". So is the above paragraph just a little
>too restrictive and should it include the colon ?

Yes, this should be disallowed as a namespace prefix... the latest
namespace draft supports this point of view.

>If not then the following
>very common XML example is illegal:
> <XML>
> This is a test.
> </XML>

Yes.

>Tim Bray's web site (http://www.xml.com/axml/axml.html) says explicitly that
>"xmlu" is an illegal name, but James Clark's expat seems to allow this ??

Well, end-users certainly shouldn't invent such names in their documents.
On the other hand, it's not clear that a processor should reject it,
because...

>Can the XML spec gurus clarify this paragraph ? Thanks.

Well, actually, the spec is a bit mushy on this; for PI targets, it
excludes "^xml*" right in the grammar, but for other names, it just
says such names are "reserved," whatever that means.

My interpretation has been that "reserved" meant, in practical terms,
reserved precisely for things like xlink and namespaces and so on;
but the spec doesn't do a good job of making this clear. I think,
Chris, you ought to get Charles or Jean to raise this formally in the
WG. -Tim