• From: ht@m... (Henry S. Thompson)
• To: John Cowan <johnwcowan@g...>
• Date: Tue, 20 Dec 2016 17:25:54 +0000

John Cowan <johnwcowan@g...> writes:

> It's mostly a grammar, but not exclusively.  In particular, subtyping by
> extension and restriction are data-model-like features that have nothing to
> do with whether a particular document conforms to a particular grammar, as
> it is always possible to compile them out of the schema.

I hesitate to disagree, but using OO-inspired techniques as a concise
way to express multiple grammar rules doesn't mean the result isn't
still a grammar -- it's just like the use of metarules in GPSG, a
notational device.  The explicit grammar is expanded by the
interpretation/application of the metarules, producing an expanded
(implicit) grammar, which is in turn what is used to determine
language membership/schema validity.

ht
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		    Henry S. Thompson, Markup Systems Ltd.
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• Follow-Ups:
  • Re: Re: Notable declarative expressions?
    • From: Thomas Passin <list1@t...>

• References:
  • Notable declarative expressions?
    • From: "Costello, Roger L." <costello@m...>
  • Re: Notable declarative expressions?
    • From: John Cowan <johnwcowan@g...>
  • Re: Notable declarative expressions?
    • From: u123724 <u123724@g...>
  • Re: Notable declarative expressions?
    • From: John Cowan <johnwcowan@g...>