Suggestion for mail to HTML 5 WG about bidirectionality markup in HTML 5

Hi all,

this is a draft mail for my action item
http://www.w3.org/2008/02/13-core-minutes.html#action01

Felix

Dear HTML Working Group,

the i18n Core Working Group has looked into the definition of the "dir" 
attribute in HTML 5 at [1] and would like to make the following comments.

1) We think that HTML 5, like HTML 4, should be able to render 
bidirectional text
without a style sheet. It would break backwards compatibility to remove
the ability of a browser to do so without CSS. Therefore in our opinion, 
HTML 5 has to
describe the expected behavior in at least the detail of HTML 4 rather than
leave it up to the "presentation layer".

2) The section about the <bdo> element does *not* leave the expected 
behavior completely up to the
presentation layer - which is confusing. Content authors need to know if 
they should use CSS, if CSS would override the specified
behavior etc.

3) We propose that you add a note making clear that using the 
bidirectionality markup provided is preferred, rather than attaching CSS 
styling to arbitrary markup such as <p> etc.

4) You should consider allowing two new attribute
values for the "dir" attribute: 'rlo' and 'lro' for dir. You do not need 
to remove the bdo element,
but the new values will allow content authors to proceed to a scenario 
we described in the ITS 1.0 specification, see [2]. It will also provide 
some additional power to the authors, since they will be able to attach 
dir="lro" to a block element.

5) Note that we do not want to impose a requirement on implementations 
of HTML 5 to implement CSS. You could just reference CSS and define a 
default stylesheet fragment. This would just mean that an HTML 5 
implementation has to make things behave as if it used this CSS default 
stylesheet
fragment.

6) HTML 4 made an exception in that it said that you don't have to 
support bidi rendering unless you actually render Arabic or Hebrew. We 
are not sure such an exception clause is still approprate, but it may be 
a way to make the adoption of the above a bit easier.

7) Further information about bidirectionality markup can be found at [3] 
and [4].

Best regards,

Felix Sasaki

[1] http://www.w3.org/TR/2008/WD-html5-20080122/#the-dir
[2] http://www.w3.org/TR/2007/REC-its-20070403/#directionality
[3] http://www.w3.org/TR/2008/NOTE-xml-i18n-bp-20080213/#DevDir
[4] http://www.w3.org/TR/2008/NOTE-xml-i18n-bp-20080213/#AuthDir

Received on Thursday, 14 February 2008 08:25:23 UTC