Re: XSchema Spec - Content Model Declarations (Section 2.3), Draft 4

John Cowan (cowan@locke.ccil.org)
Mon, 13 Jul 1998 12:20:37 -0400


Ron Bourret wrote:

> The first aim is to provide what I will call an instance syntax -- that is, the
> syntax of an XML document that people should follow exactly. The second aim is
> to provide a bag of definitions that can be used elsewhere. Note that while
> XSchemas in the first case can, with a bit of work, be reused as the second
> case, the opposite is unlikely to be true.

Just so.

> Our current syntax satisfies the first aim. John's first suggestion satisfies
> the second aim. The XSchema subelement is a mechanism for grouping definitions:
> a group of attributes (negates the need for AttGroup),

You're right. I withdraw AttGroup; XSC:XSchema does it all.

> "... The XSC:XSchema element may also contain other XSC:XSchema elements nested
> inside of it. ****This allows one XSchema document to contain other XSchema
> documents. It also serves as a way to group XSchema elements for inclusion in
> other XSchema documents.****"

Good.

> 2) As John suggests, expand the legal elements beneath an XSchema element. In
> particular, add AttDef, Choice, Sequence, Mixed, and Ref to the XSchema
> element. (NotationType and EnumerationType no longer exist. I have added Ref
> to John's list.)

My only criticism: I don't think Ref belongs here, simply because Refs
don't have any content themselves: they are just pointers, so it seems
useless, over-complicated, and confusing in XSchema to have pointers
to pointers.

-- 
John Cowan	http://www.ccil.org/~cowan		cowan@ccil.org
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)