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Re: use of literal 'pi' in cn example (section 4.4.1.1.3)

From: David Carlisle <davidc@nag.co.uk>
Date: Thu, 23 Jan 2003 13:44:39 GMT
Message-Id: <200301231344.NAA05456@penguin.nag.co.uk>
To: Michael.McCarthy@solcorp.com
CC: www-math@w3.org


  1) if the intention is to refer to a symbol called 'pi', then the
  appropriate mechanism is to use the <csymbol/> element instead of using the
  <cn/> element
  2) this constant is already defined as <pi/>

I think that's probably true (now). The example dates from mathml 1 which
didn't have either <csymbol> or <pi/>. So as you commented, it's
definitely still legal but I think almost all the uses for which
 <cn type="constant" was intended could better be done with the newer
MathML2 Content elements such as <pi/> or with <csymbol>. so this usage
probably should be deprecated. (Now is a good time to raise such issues
as we are working on a draft of mathml2 2nd edition....)

  Since the grammar does not say what type="constant" means,

The grammar doesn't, but 4.3.2.9 on the type attribute does say more
about this (and would need changing if your suggestion to deprecate this
usage was accepted).

 
David
(personal opinion: not discussed this with the other WG members yet)

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Received on Thursday, 23 January 2003 08:45:06 GMT

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