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Re: content markup newbie questions

From: David Carlisle <davidc@nag.co.uk>
Date: Wed, 17 Sep 2008 21:51:31 +0100
Message-Id: <200809172051.m8HKpVVQ010407@edinburgh.nag.co.uk>
To: prushfor@NRCan.gc.ca
Cc: www-math@w3.org


Unfortunately in a way, <declare> isn't widely supported by rendering
agents, certainly the ctop.xsl stylesheet that you mentioned just
discards it. This is conformant but perhaps less helpful than you may want.

As far as presentation goes <declare> even if fully implemented just
gives a hint that the declared symbols, when they occur later in the
expresssion, should be rendered differently. The declare expression
itself isn't expected to be rendered.

Thus the default rendering of your math expression, which only consists
of declare is empty.


The main problem with declare is that a useful declaration maechanism
needs to have (at least) document scope but mathml itself can only 
define a single math element. If defining a compound document format
that uses mathml for math fragments in a larger document context it is of
course possible to define things with a wider scope (see for example
omdoc as an example) and hopefully one day we'll get  defined profile of
xhtml+mathml with that kind of functionality built in.

However today, For use in a web browser, I'd mark up the definitions
that you posted as equations rather than using declare.

David

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Received on Wednesday, 17 September 2008 20:52:06 GMT

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