But if they're general entities in XSchema, then they get parsed in
context, and their type is enforced by the XSchema DTD. Picture this:
XSchema with XSchema DTD, before non-DTD entity mechanisms:
<?xml version="1.0"?>
<?xml:namespace ns="http://www.purl.org/NET/xschema" prefix="xsc"?>
<!DOCTYPE xsc:xschema
SYSTEM "http://www.purl.org/NET/xschema/xschema.dtd" [
<!ENTITY para.content
"<xsc:mixed>
<xsc:element idref="emph"/>
<xsc:element idref="literal"/>
<xsc:element idref="term"/>
</xsc:mixed>">
]>
<xsc:xschema>
<xsc:elementdecl id="para">
¶.content;
</xsc:elementdecl>
</xsc:xschema>
This is a bit ugly, but it's clean: the type of a "parameter" entity
is validated because it's parsed in context. Unlike DTD parameter
entities, they have to be declared in the prolog to the schema, but
that makes parsing cleaner. But then, once there's a non-DTD way to
declare entities:
<?xml version="1.0"?>
<?xml:namespace ns="http://www.purl.org/NET/xschema" prefix="xsc"?>
<?xml:namespace ns="http://www.purl.org/NET/xents" prefix="xent"?>
<my-document-bag>
<xent:entitydecl id="para.content"><![CDATA[
<xsc:mixed>
<xsc:element idref="emph"/>
<xsc:element idref="literal"/>
<xsc:element idref="term"/>
</xsc:mixed>
]]></xent:entitydecl>
<!-- this is one example of why I think that you shouldn't try to
tackle entity declarations just yet... -->
<xsc:xschema>
<xsc:elementdecl id="para">
¶.content;
</xsc:elementdecl>
</xsc:xschema>
</my-document-bag>
-Chris
-- <!NOTATION SGML.Geek PUBLIC "-//Anonymous//NOTATION SGML Geek//EN"> <!ENTITY crism PUBLIC "-//O'Reilly//NONSGML Christopher R. Maden//EN" "<URL>http://www.oreilly.com/people/staff/crism/ <TEL>+1.617.499.7487 <USMAIL>90 Sherman Street, Cambridge, MA 02140 USA" NDATA SGML.Geek>