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The MathML documentation is broken

From: Thomas Fischbacher <Thomas.Fischbacher@Physik.Uni-Muenchen.DE>
Date: Thu, 20 May 2004 21:26:53 +0200 (CEST)
To: www-math@w3.org
Message-ID: <Pine.LNX.4.58.0405202126360.28574@seekar.cip.physik.uni-muenchen.de>


If a MathML newbie like me has a very specific problem, such as 
auto-generating XML code to display formulae with lots of overbars and 
such in them, then _certain_ pages such as

http://www.w3.org/Math/testsuite/testsuite/Presentation/TokenElements/mo/moAaccent10.xml

are - to state it mildly - less than helpful by lying about what's going on.

We see on this page (if viewed with a MathML enabled browser) a formula 
with a few overbars in it, and below a block of XML code that claims to be 
the source for that formula. Alas, it is not.

Rather, the math part is:

      <mrow> 
        <mover> 
          <mrow> 
            <mi>G</mi> 
            <mo>-</mo> 
            <mn>1</mn> 
          </mrow> 
          <mo accent="false">&#x000AF;</mo> 
        </mover> 
        <mo accent="false">+</mo> 
        <mover accent="true"> 
          <mrow> 
            <mi>G</mi> 
            <mo>-</mo> 
            <mn>1</mn> 
          </mrow> 
          <mo accent="false">&#x000AF;</mo> 
        </mover> 
        <mo accent="true">+</mo> 
        <mover accent="false"> 
          <mrow> 
            <mi>G</mi> 
            <mo>-</mo> 
            <mn>1</mn> 
          </mrow> 
          <mo accent="false">&#x000AF;</mo> 
        </mover> 
      </mrow> 
    </math>

and the text claims the math part to be:

    <pre>
    &lt;math> 
      &lt;mrow> 
        &lt;mover> 
          &lt;mrow> 
            &lt;mi>G&lt;/mi> 
            &lt;mo>-&lt;/mo> 
            &lt;mn>1&lt;/mn> 
          &lt;/mrow> 
          &lt;mo accent='false'>&amp;OverBar;&lt;/mo> 
        &lt;/mover> 
        &lt;mo accent='false'>+&lt;/mo> 
        &lt;mover accent='true'> 
          &lt;mrow> 
            &lt;mi>G&lt;/mi> 
            &lt;mo>-&lt;/mo> 
            &lt;mn>1&lt;/mn> 
          &lt;/mrow> 
          &lt;mo accent='false'>&amp;OverBar;&lt;/mo> 
        &lt;/mover> 
        &lt;mo accent='true'>+&lt;/mo> 
        &lt;mover accent='false'> 
          &lt;mrow> 
            &lt;mi>G&lt;/mi> 
            &lt;mo>-&lt;/mo> 
            &lt;mn>1&lt;/mn> 
          &lt;/mrow> 
          &lt;mo accent='false'>&amp;OverBar;&lt;/mo> 
        &lt;/mover> 
      &lt;/mrow> 
    &lt;/math>
  </pre>

Please notice that the displayed text claims that the XML source uses

         <mo accent='false'>&OverBar;</mo>

while indeed, it _does_ use

          <mo accent="false">&#x000AF;</mo>

Not only that the documentation makes obviously false claims here - 
which is a sin by itself - the &OverBar; construction does _not_ work with
e.g. the Mozilla version in Debian GNU/Linux 3.0 (Woody).


Now, wouldn't it be much simpler, better, nicer, easier, and more 
reliable to auto-generate the "Source is ..." part from the XML math code? 
After all, if XML is such a hot thing, this should be no big issue at 
all, right?

-- 
regards,               tf@cip.physik.uni-muenchen.de              (o_
 Thomas Fischbacher -  http://www.cip.physik.uni-muenchen.de/~tf  //\
(lambda (n) ((lambda (p q r) (p p q r)) (lambda (g x y)           V_/_
(if (= x 0) y (g g (- x 1) (* x y)))) n 1))                  (Debian GNU)
Received on Thursday, 20 May 2004 15:26:57 GMT

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