Peter Kirk
Thu, 14 Aug 2003 12:17:55 -0700
Kenneth Whistler wrote:Not true, as we have seen for Hebrew. It's supposed to be true, but isn't, and the problems can't be fixed.
Kent Karlsson said:
I see no particular *technical* problem with using WJ, though. Inanywhere else but
contrast
to the suggestion of using CGJ (re. another problem)
at the end of a combining sequence. CGJ has combining class0, despite
being invisible and not ("visually") interfering with any otherWhy?
combining
mark. Using CGJ at a non-final position in a combining sequence puts
in doubt the entire idea with combining classes and normal forms.
See above (I DID write the motivation!). Combining classes are generally assigned according to "typographic placement". Combining characters (except those that are really letters) that have the "same" placement, and "interfere typographically" are assigned the same combining class, while those that don't get different classes, ...
There is no difference when the characters really do not interfere typographically. But when they do, there is a real and, in some languages, meaningful distinction.... and the relative order is then considered unimportant (canonically equivalent). How is then, e.g. <a, ring above, cgj, dot below> supposed to be different from <a, dot below, cgj, ring above> (supposing all involved characters are fully supported), when <a, ring above, dot below> is NOT supposed to be much different from <a, dot below, ring above> (them being canonically equivalent)? ...
...OK, let's confine it to those specific uses where it is really needed, e.g. to get round the problem of combining characters with different combining classes which actually do interact typographically, and perhaps there was another one being suggested. I have no problem with that - as long as the list of permitted uses is not set in stone, so that new uses can be approved when they are discovered. But there is no good reason to object to its use in those cases where it is needed, simply because in many other cases it is not needed.
... the only ways out seem to be to either formally deprecate
CGJ, or at least confine it to very specific uses. Other occurrences
would not be ill-formed or illegal, but would then be non-conforming.
-- Peter Kirk [EMAIL PROTECTED] http://web.onetel.net.uk/~peterkirk/