Re: per-paragraph auto-direction, a.k.a. dir=uba

(a) Just wish to mention that the UAX#9 default algorithm does ignore
neutrals ("*P2. In each paragraph, find the first character of type L, AL,
or R.")* - we might want to stick to that default if consensus cannot be
reached (i.e. ignore all weaks and neutrals).

(b) I probably misunderstand something:
 returning rtl for an element containing only AN numbers is not the same as
ignoring AN (which would give the inherited direction, possibly ltr).

(c)  It took a while till I figured out the significance of *negative* AN
numbers, so I repeat here in case other people missed that too:
      if the element contains "-123" (where figures here represent
Arabic-Indic numerals), and the direction is RTL, it is displayed as "123-".
However in LTR paragraph direction it is displayed as "-123". This might be
the reason why the exception regarding weak ltr charcters was added (I had
hard time figuring out why it was added before).

    Amit

On Mon, Sep 27, 2010 at 11:01 AM, Aharon (Vladimir) Lanin <aharon@google.com
> wrote:

> That is actually the same as just ignoring AN characters in first-strong. I
> am fine with doing that unless there is a strong response from an Arabic or
> Farsi speaker saying that negative AN numbers definitely do need to be
> displayed in LTR, since (as we have seen) AN phone numbers come out the same
> in LTR and RTL. Make it soon, since I need to get this finalized today.
>
> Aharon
>
>
> On Sun, Sep 26, 2010 at 10:55 PM, CE Whitehead <cewcathar@hotmail.com>wrote:
>
>>
>>
>> From: Aharon (Vladimir) Lanin <aharon@google.com>
>> Date: Sun, 26 Sep 2010 02:01:23 +0200
>>
>> >      - The first-strong algorithm returns the direction of the first
>> > strong
>> >      (L, AL, or R) character it encounters. If it does not encounter
>> any,> it
>> >      returns ltr if it encounters any weak ltr characters (EN or AN).
>> I disagree slightly here; I think it should return ltr except for an for
>> which I would prefer-- I guess -- that it return rtl unless there is an
>> inherited dir of ltr
>> Best,
>> --C. E. Whitehead
>
>
>