Hangul jamos [was: Re: logos, symbols, and ligatures (RE: Encoding Personal Use Ideographs)]

Kent Karlsson wrote:
> And yet the UTC, as well as WG2, seems to be in the process of adopting 100+
> Hangul Jamo that are aren't even ligature-like, but each just represents a sequence
> of Hangul conjoining letters.
>   

IMHO, this is the predictable and inevitable result of the canonical 
decompositions which have been frozen in Unicode 3.1.

Since that day, the standard says that they are three different coded 
character sequences to represent 갂:

S = <AC02>
LVT=<1100 1161 11A9>
LVTT=<1100 1161 11A8 11A8>

with S and LVT canonically equivalent but not equivalent to LVTT. The 
bulk of the data that exists today uses S/LVT; where "bulk" is probably 
99%. The idea of LVTT, however sensible and desirable, did not happen in 
practice. Because 11A9 is not and cannot be made canonically equivalent 
11A8, 11A8, I believe that the only sensible course of action is to 
admit that the idea of L+, V+, T+ in a syllable did not succeed, and 
continue down the path of "complex" jamos (such as 11A9). I would even 
recommend to deprecate the use of multiple "simplex" jamos in each part 
of a syllable, as a way to resolve the problem of multiple 
non-equivalent representations, and the implementation problems that 
causes (In fact, I am ready to bet that most implementations simply 
treat LVTT as different from S/LVT, one more reason for cleaning the 
standard.)

I think the alternative you prefer (keep using <11A9>, but do not create 
new combinations like that) would not result in a system that is clean 
from a model point of view, nor in a system that is clean from an 
implementation point of view. So I don't see anything that makes it 
desirable.


Eric.