Re: Caret

What is not rare is the insertion between strong and weak directions. What
is rare is the insertion between two characters with opposite strong
directions.

I think it's appropriate to maintain this distinction for the practical
case, and the expected user-friendly behavior of editors when editing text
notably at the weak position bordered by a weak SPACE or start/end of a
paragraph, for which the character with the strongest direction should
still win:

It is arguably, by very far, the most frequent case, even if "rare" does
not mean a precise statistic that you won't encounter this case everyday
(and that most users won't care about when they rarely type text using
alternanace of directions without at least a weak space separation).

I also counted the case of strong Perso-Arabic digits, which behave a bit
differently from Euro-Arabic digits which are weaker (so they loose if they
are sticked with Arabic letters which should still dictate the expected
direction if insertion/deletion without ambiguity). If there are
Perso-Arabic digits sticked with Arabic letters, there's no ambiguity, the
whole is strongly RTL and a single caret is also enough (even if you may
still indicate the direction of this single caret with an arrow head)

The appearance of dual position carets should be limited as most as
possible to only the very ambiguous cases like "latinARABIC" or
"ARABIClatin" where the insertion point is between the two strong scripts,
and that should then be displayed (respectively) not as

  latin|CIBARA
  CIBARA|latin

but as

  latin_^CIBARA
  ^CIBARAlatin_

(here again, "_" is the right-side insertion caret pointing to the right,
and "^" is the left-side insertion caret pointing to the left)
Received on Mon Nov 12 2012 - 15:55:12 CST