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Re: When to stretch parentheses

From: Luca Padovani <lpadovan@cs.unibo.it>
Date: Fri, 30 Jan 2004 11:59:40 +0100
To: www-math@w3.org
Message-Id: <1075460380.15093.34.camel@giraffe>

Hi Vincent,

On Fri, 2004-01-30 at 11:36, Vincent Quint wrote:
> Section 3.2.5.8.2 of the MathML 2.0 spec (2nd edition) "Vertical Stretching
> Rules", first bullet, says:
> "If a stretchy operator is a direct sub-expression of an mrow element,
> ....then it should stretch to cover the height and depth (above and below
> the axis) of the non-stretchy direct sub-expressions in the mrow element..."

The last item in the same list says

" The preceding rules also apply in situations where the mrow element is
inferred."

Section 3.1.3.1 is more precise than 7.1.2 about the math element:

"The elements listed in the following table as requiring 1* argument
(msqrt, mstyle, merror, menclose, mpadded, mphantom, mtd, and math)
actually accept any number of arguments. However, if the number of
arguments is 0, or is more than 1, they treat their contents as a single
inferred mrow formed from all their arguments"

so the parentheses should be stretched. In this respect Amaya's
rendering is the correct one. Note however that the sample markup is not
properly grouped. I would have expected to have the CM identifier in its
own mrow element:

...
<mrow>
  <mo>(</mo>
  <mi>CM</mi>
  <mo>)</mo>
</mrow>
...

or equivalently inside an <mfenced> element.

--Luca 
Received on Friday, 30 January 2004 05:59:49 GMT

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