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Re: isotech error with lowast?

From: Bruce Rosenblum <bruce@inera.com>
Date: Thu, 12 Nov 2009 15:59:44 -0500
Message-id: <0KT000EDOKZOT8ZX@vms173017.mailsrvcs.net>
To: David Carlisle <davidc@nag.co.uk>
Cc: www-math@w3.org,btusdin@mulberrytech.com,dalapeyre@mulberrytech.com
David,

Thanks for the clear and complete explanation. It's helpful, and I 
appreciate your time to reply.

Best regards,

Bruce

At 12:45 PM 11/12/2009, David Carlisle wrote:

> > Shouldn't this be defined as:
> >
> > <!ENTITY lowast           "&#x0204E;" ><!--low asterisk -->
>
>One might expect that, but like some others (most notably asymp) the
>definitions are somewhat skewed by html compatibility. Many of the html4
>entity definitions are somewhat strange but the html4 symbol.ent file
>linked from
>
>http://www.w3.org/TR/html4/sgml/dtd.html
>
>defines lowast to be
>
><!ENTITY lowast   CDATA "&#8727;" -- asterisk operator, U+2217 ISOtech -->
>
>The html entity sets are baked into code in multiple browsers of every
>desktop and mobile phone on the planet and nothing that is put in a dtd
>entity file will change that as most html systems don't read these
>definitions from any kind of declarative file, thus is seems futile to
>publish an html dtd with definitions different from the ones actually
>implemented, and it would be odd to try to make xhtml incompatible to
>html with respect to entity definitions.
>
>If the mathml set were incompatible with xhtml then the meaning of lowast
>throughout an xhtml+mathml document would depend on the technical
>details of how the dtds were combined, but whichever definition "won" it
>would mean the same thing throughout the document, you can't make the
>expansion of the entity sensitive to which element the entity is in.
>
>The main aim of taking the entity set definitions out of mathml into
>their own spec at
>
>http://www.w3.org/TR/xml-entity-names/
>
>is to get a common set of definitions that can be used accross
>languages, but where existing usage in different communities is
>incompatible, getting a common set means something has to change and the
>above considerations mean that essentially if there was a conflict the
>html definition was taken.
>
>I hope that explains why things are as they are
>
>David
>
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Bruce D. Rosenblum
Inera Inc.
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Newton, MA 02460
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bruce@inera.com 
Received on Thursday, 12 November 2009 21:00:32 GMT

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