Open ntounsi opened 7 years ago
As far as I remember, the difference in bidi category between Arabic-Indic digits and Eastern Arabic-Indic digits is due to the difference in bidi behavior desired in Arabic vs. Persian. Details should be available from Unicode.
http://unicode.org/reports/tr9/#AN Section : 3.2 Bidirectional Character Types "[...]
I guess the "few Indic characters" are the Eastern Arabic-Indic digits in range U+06F0..U+06F9, which are classified "European Number" vs "Arabic numbers". I wonder what is the "canonical equivalence" problem in question. Didn't find more details.
I think it is referring to characters used for Indic languages, not the Arabic-Indic digits which AFAIK had this distinction from the start.
@shervinafshar and I had a discussion about this years ago here: https://groups.google.com/forum/#!topic/persian-computing/602gqTIrlPQ because I found Arabic-Indic Extended to suit better for our use on a special case (but maybe is better on other cases).
I remember @roozbehp (which I guess won't get pinged by my mentioning here), somewhere on a very old mailing list discussion, something like 2001(?), wrote he was explaining to a developer why these are different, so if my memory on this is correct, perhaps he would be a good person to ask about the reason of the difference.
Are all numbers equal in category and directional property?
There is also a difference in Bidi behavior : the same visual text
will be displayed in RTL context as
if
is Arabic number, and
, if European number (simply like "a 2 b"). Aren't ALL numbers WEAK in directional property?