Re: meta-specs (was RE: A few things I noticed about w3c's xml-schema)

[Jonathan Borden <jborden@mediaone.net>]

Joel Rees wrote:

> Iwaku Jonathan Borden:
>
>
> > As you stick each of your documents into the boxes you find that for two
> of
> > the boxes, half the documents cause the box to light up and for the
other
> > two boxes the other half of the documents cause the box to light up. You
> now
> > have your two groups of documents, and two groups of schemata. We say
each
> > of the schema in the group is "equal" because they each have the same
set
> of
> > instance documents.
>
> Is this ability to compare instances assumed to be hypothetical, or can it
> actually be implemented for some subset of instances?
>

It can be easily implemented for some subset of documents. An instance
validator for a schema language indicates whether a document is "valid" with
respect to a schema. For a DTD, this is implemented by a validating parser.

-Jonathan