W3C home > Mailing lists > Public > www-math@w3.org > October 2003

rangle and langle in math discouraged

From: David Allouche <david@allouche.net>
Date: Fri, 24 Oct 2003 18:22:46 +0200
To: www-math@w3.org
Cc: Joris van der Hoeven <vdhoeven@texmacs.org>
Message-ID: <20031024162246.GA6571@nemesis.xlii.org>

Hello,

I am currently working on conversion tables between TeXmacs symbols and
Unicode in order to improve XML (and MathML) export.

MathML defines:
<!ENTITY lang "&#x02329;" ><!--/langle O: left angle bracket -->
<!ENTITY rang "&#x0232A;" ><!--/rangle C: right angle bracket -->

However the unicode chart states:
http://www.unicode.org/charts/PDF/U2300.pdf

  These are discouraged for mathematical use because of their canonical
  equivalence to CJK punctuation.

Instead, the recommanded codes for mathematical use are
(from the unicode database)
27E8;MATHEMATICAL LEFT ANGLE BRACKET;Ps;0;ON;;;;;Y;;;;;
27E9;MATHEMATICAL RIGHT ANGLE BRACKET;Pe;0;ON;;;;;Y;;;;;

Since texmacs is most probably going to use the same conversion tables
for generic XML (where I would prefer to use the unicode recommanded
characters) and for MathML (where using the character corresponding to
the entity is definitely the right thing) I am quite annoyed since there
seem to be no right solution...

Do I have missed something in the MathML recommandation? Is there a
rationale for using these characters for MathML even though this is
discouraged by Unicode? Is it planned that MathML be updated?


Thanks for your help.
-- 
                                                            -- ddaa
Received on Friday, 24 October 2003 12:22:47 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 20 February 2010 06:12:55 GMT