[HarfBuzz] Backspace and Delete behaviours

[Behdad Esfahbod]

On 07/24/11 05:02, Rajeev J Sebastian wrote:
> On Sun, Jul 24, 2011 at 9:00 AM, Behdad Esfahbod <behdad at behdad.org> wrote:
>> On 07/23/11 12:06, Rajeev J Sebastian wrote:
>>> whereas backspace erases logical characters.
>>
>> This is vague and wrong.  What's a logical character?  If you simply mean
>> Unicode character, then there's a trivial reason for why this is wrong:
>> ideally user shouldn't know or care about the difference between NFC and NFD.
>>  Backspace, delete, cursor movement, all should ideally work the same with
>> NFC, NFD, or any other canonically equivalent Unicode text.
>>
>> And, one size does not fit all.  For example, Arabic non-spacing marks are
>> vowel marks that one would expect to be able to back-space, but say, grave
>> accent, or any of the other Latin marks, are diacritic marks, not vowels.
>> They simply _modify_ their base, so user expects backspace to delete the mark
>> and the base.
> 
> Im referring to Indic scripts here.

The NFC/NFD case equally applies to Indic split matra characters.

behdad

> Regards
> Rajeev J Sebastian
>