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Re: And the DTD says, "I'm NOT dead yet!!"
- From: Caroline Clewlow <firstname.lastname@example.org>
- To: Norman Walsh <email@example.com>
- Date: Tue, 09 Jan 2001 15:01:36 +0000
Is this something that RELAX takes care of with it's <elementRule role=""
whereby two element rules can have the same role with a different label
depending on how they constrain their child elements ?
I'm no expert here - just throwing ideas onto the fire ;-)
Norman Walsh wrote:
> / Bob Kline <firstname.lastname@example.org> was heard to say:
> | don't think this is one of them. The most common uses I have seen for
> | entities are:
> | 1. to create macros for commonly used content-model groups; and
> | 2. to create a kludge for working around the lack of support for
> | namespaces in DTDs.
> | The first is handled fairly well by named groups (<xsd:group name=...)
> | and the second problem doesn't exist because XML Schema supports
> | namespaces. External entities in DTDs correspond pretty well to the
> | <xsd:include ...> element in XML Schema.
> The significant feature that seems to be missing, but might be addressed
> with <redefine> if it's extended to allow complete redefinition of
> model groups and attribute groups (i.e., redefinition without reference
> to the original), is the ability to change the groups in derived schemas.
> Suppose I have the following PE in my DTD:
> <!ENTITY % article.content "para|note|warning">
> I can easily construct a derived DTD that does not allow warnings:
> <!ENTITY % original.dtd SYSTEM "...">
> <!ENTITY % article.content "para|note">
> It's not clear that I can do this with XML Schemas, and I do this *a lot*.
> Be seeing you,
> Norman.Walsh@East.Sun.COM | There has never been a perfect government,
> XML Technology Center | because men have passions; and if they did
> Sun Microsystems, Inc. | not have passions, there would be no need
> | for government.--Voltaire