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Re: e-notation definition missing from MathML 2nd ed schemas?

From: David Carlisle <davidc@nag.co.uk>
Date: Thu, 13 May 2004 10:04:31 +0100
Message-Id: <200405130904.KAA21374@penguin.nag.co.uk>
To: mhucka@caltech.edu
Cc: jsdevitt@stratumtek.com, www-math@w3.org



  Your message reminds me of something else: I forgot to
  mention that I also looked at the DTD for MathML 2, and it
  does not appear to define e-notation either.

The DTD  does not constrain the value in any way, so (unlike the case
with the schema that you reported) e-notation is allowed.
Note this actually matchess the prose text of the spec which does
specify this as an open list with some pre-defined possibilities.
By having it unconstrained in the schema/dtd you allow extension but
also don't catch typos (which are more common) The approach taken (here
and more generally in the schema) is to have a tighter schema and if you
extend the list of type names you need to extend the schema that you are
using to match.

mainly the DTD takes the other approach that the DTD is rather lax.
There is a MathMLStrict option in the dtd (see the description in
appendix A) which does tighten up many things (eg forcing mfrac to have
exactly two children) and could have constrained this list but currently
it does not.

David

-- 
The LaTeX Companion
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  http://www.amazon.co.uk/exec/obidos/tg/detail/-/0201362996/202-7257897-0619804


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Received on Thursday, 13 May 2004 05:05:01 GMT

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