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Re: 'dir' attribute on BIDI inline elements and actual browsers

From: Helmut Wollmersdorfer <helmut@wollmersdorfer.at>
Date: Wed, 20 Dec 2006 15:29:13 +0100
Message-ID: <458948B9.1090801@wollmersdorfer.at>
To: www-html@w3.org

Paul Nelson (ATC) wrote:
> The Unicode Bidirectional algorithm(http://www.unicode.org/reports/tr9/)
> provides the guidance on how to process this. The correct layout is [1].

Unicode BIDI is the low level protocol, which cannot give an answer 
about HTML.

> Because the Hebrew is a RTL script, the addition of the span does
> nothing to change the layout. One could just as easily have put: 

> <p>English1 &#1506;&#1489;&#1512;&#1497;&#1514;2. 
> &#1506;&#1489;&#1512;&#1497;&#1514;3 
> Englisch4.</p>

A first reader of http://www.w3.org/TR/html401/struct/dirlang.html#h-8.2 
will only mark the Hebrew words with 'dir', similar to the well known 
usage of other inline markup, e.g. <b> or <em>. And he would expect the 
'. ' (dot-space) to be in the style of the parent element.

In the specs of HTML the above enclosing is given as example:

| Thus, to express a Hebrew quotation, it is more intuitive to write
| <Q lang="he" dir="rtl">...a Hebrew quotation...</Q>

If the authors of the HTML spec intended layout [1], then this is not 
'KISS' (Keep It Simple, Stupid). This needs a HTML author to know the 
details of the Unicode BIDI algorithm, especially all the neutral and 
weak characters.

Another symptom, that this part of the HTML spec needs re-design and/or 
re-wording, is the large amount of test cases, FAQs, bugs, inconsistancy 
across browsers etc.

> If you wanted the layout of [2], you can do the following to force the
> right bidirectional embedding:

> <p>English1 &#1506;&#1489;&#1512;&#1497;&#1514;2. 
> <span dir=ltr>&#1506;&#1489;&#1512;&#1497;&#1514;3 
> Englisch4.</span></p>

This is not an intuitive solution. Common sense would place the <span 
...> between '2' and '.', because the neutral '. ' should be forced LTR. 
Or include only the '. ' into a <span ...>.

Helmut Wollmersdorfer
Received on Wednesday, 20 December 2006 14:29:45 UTC

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