FW: Offer of advice

Title: FW: Offer of advice

FYI -- for this morning's 
discussion.

From: Ray Lam 
[mailto:] 
Sent: Sunday, March 19, 2006 
11:09 PM
To: Paul Prescod; 
Cc: JoAnn 
Hackos
Subject: RE: Offer of advice

Gershon and I did discuss the 
use of the xml:lang attribute for inferring directionality, and it seems to me 
that xml:lang could be useful for basic support of the bidi algorithm, but it 
may break down if it was used to handle the more complex cases of bidirectional 
text.

 

For instance, there might be cases where 
the default embedding level may not be equivalent to that of the language. For 
instance, in a primarily Arabic document there might be a single paragraph 
that is predominantly English (starts and ends in English, but with some Arabic 
content nested within), but the author of the article wishes the default 
embedding level to be right-to-left so that it flows consistently with the rest 
of the article, then an xml:lang attribute of "English" on that paragraph will 
contradict with the wishes of the author. Using a dir attribute of rtl would 
meet his particular needs.

 

Also, the use of the xml:lang by itself may 
not be sufficient to determine directionality. Numeric sequences for instance 
are still rendered left-to-right in languages like Hebrew and Arabic, and an 
xml:lang setting of "Hebrew" would still impose a burden on the processor to 
understand that numeric runs would be rendered in a direction counter to the 
natural direction of the language. Tagging these numeric sequences with an 
xml:lang of "English" or another left-to-right language just to get 
left-to-right rendering would seem counter-intuitive to me.

 

One other thing, xml:lang does not have the 
notion of directional overrides  - probably arguable how useful this 
feature actually may be - but nonetheless a feature of the bidi 
algorithm that would be difficult to reproduce using just the xml:lang 
attribute.

 

So, in my opinion, the use of the xml:lang attribute will probably 
be useful for translation purposes and possibly for basic support of 
directionality, but I believe that using the dir attribute will be a cleaner, 
more powerful and more explicit means for specifying directionality.

 

Ray

From: Paul Prescod
Sent: Thu 
16/03/2006 11:29 AM
To: Ray Lam; 
Cc: 
JoAnn Hackos
Subject: FW: Offer of advice

I think you two know each other already! I don't have time to 
participate in all of these discussions but Ray knows what requirements we came 
up with based on our conversations with customers, partners and experts and may 
have some thoughts to contribute on the discussions.

-----Original 
Message-----
From: JoAnn Hackos [mailto:]
Sent: 
Thursday, March 16, 2006 6:28 AM
To: Paul Prescod; Don Day
Subject: RE: 
Offer of advice

Paul,
Could you put him in touch with Gershon so that 
he sees the debate going on about the dir attribute? I've attached the last of 
the email threads.
JoAnn

-----Original Message-----
From: Paul 
Prescod [mailto:]
Sent: 
Tuesday, March 14, 2006 10:53 AM
To: JoAnn Hackos; Don Day
Subject: Offer 
of advice

I'd be glad to offer XMetaL's bidi expert for consultation on 
your bidirectionality discussions if this is of value to you. We went to 
considerable effort to research the best practices and state of the art before 
implementing our bidirectionality support.

 Paul 
Prescod