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Re: Update on namespaces

From: Matthew Fuchs <matt@wdi.disney.com>
Date: Fri, 27 Jun 1997 12:56:22 -0700
Message-Id: <9706271256.ZM16466@scrumpox.rd.wdi.disney.com>
To: <w3c-sgml-wg@w3.org>
On Jun 28,  5:33am, Rick Jelliffe wrote:
> Subject: Re: Update on namespaces
>
> > From: Matthew Fuchs <matt@wdi.disney.com>
>
> > After thinking about it a bit, I thought that something like #OTHER
> was also
> > generally too loose, which is why my proposal on validation and
> namespaces
> > allowed you to specify which namespace to use.  After all, CML might
> import
> > several different namespaces, but at some particular point you want
> to specify
> > there should be an equation here.  If you can designate the namespace
> (i.e.,
> > <!ELEMENT html ( head, (body | frameset | layer | MATH:: ), tail )
> >), you can
> > ensure that.
>
> I had been thinking of that too, however it seems to me that if you
> already know that you want to allow some element types from NAME::, you
> already have a good idea of which ones you want to allow, so you are
> not in fact getting in extra functionality, just some sugar.  After
> all, you probably just want:
>
> <!ELEMENT html (head (body|frameset|layer|MATH::eqn|MATH::inlinef),
> tail)>
>
> which is why MATH:: or  MATH::#ANY  (my preferred syntax for that) does
> not serve as much use as it first seems. As Eve Maler's book suggests,
> you get "information units" with element that do not serve much purpose
> if take separately.  I think XML/SGML should seek to support arbitrary
> inclusions of the top level elements of information units in
> particular, which is what I think AndrewL might concur with.
>

Well, yes and know.  This assumes you (or rather, the DTD designer) know the
structure of the namespace you are refering to.  Suppose I have a document in
which will be stuck (not necessarily by me) a motion picture type rating and/or
a secure signature.  There may be several rating systems and several secure
signatures systems, depending on which country the document will be viewed in,
the material being reviewed (i.e., motion picture vs. tv), etc.  The signature
may be put in by my email agent and even translated from one protocol to
another as it moves among legal domains.  The DTD designer should be able to
say "the rating goes right here" without necessarily knowing what its exact
form will be. This is why my proposal went out of its way to support very late
binding.  I think we're going to need that for a lot of applications.  So I do
think you get some added value from MATH::

Matthew Fuchs
matt@wdi.disney.com

-- 
Received on Friday, 27 June 1997 15:54:28 EDT

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