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Re: empty set symbol in MathML

From: William F Hammond <hammond@csc.albany.edu>
Date: Mon, 05 Apr 2004 13:42:10 -0400
To: W3C MathML Development Discussion <www-math@w3.org>
Message-ID: <i7smfie2z1.fsf@hilbert.math.albany.edu>

Robert Miner <RobertM@dessci.com> writes:

> Other experts will correctly me if I'm wrong, but my memory is that
> Unicode doesn't acknowledge these as separate character. Instead, they
> are regarded a "glyph variants" of the same character, and thus they
> do not get separate code points.
> . . .
> Consequently, apart from the inherently fragile <mglyph> construct,
> there is no good way to distiguish these characters within MathML.

Specific things that are important enough to trigger such discussion
here could be made non-fragile if they had existence in MathML as
empty elements.  A few examples suggested by LaTeX include
<leftarrow/>, <longleftarrow/>, <rightarrow/>, <longrightarrow/>,
<mapsto/>, and <longmapsto/>.

I don't imagine more than a few hundred of such empties.

                                    -- Bill
Received on Monday, 5 April 2004 13:42:23 GMT

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