Contrastive use of kratka and breve

Philippe Verdy verdy_p at
Wed Jul 2 14:40:52 CDT 2014

2014-07-02 20:55 GMT+02:00 Jukka K. Korpela <jkorpela at>:

> I think the idea of using CGJ is more wrong than the idea of using ZWNJ.

I think exactly the opposite. CGJ brings the distinction that it prohibits
the cannical combination. As the resulting string is not anonically
equivalent, it is also semantically distinctive.

Note that we are in the case were CGJ would be used here just after a base

We are not in the situation where CGJ is used between TWO combining
characters, where the first one has a *higher* combining class than the
second one with a non-zero combining class (this case is where CGJ is used
to prevent reordering of combining diacritics during normalization: this
case occurs when these diacritics wbich usually don't interact with most
base characters may collide on the same position and need an explicit
difference, for example when the cedilla occurs above a letter rather than
below it and interacts with another diacritic above that letter, and the
relative order of the cedilla and that diacritic matters). This is used
notably in the Hebrew script (due to the "strange" historic assignment of
distinct non-zero combiing classes to most of its diacritics even when they
can interact and relative ordering is significant both semantically and

We are also not in the situation where CGJ occurs between TWO combining
characters having the *same* combining class, in order to stack them
differently. In that case, no reordering occurs, even without CGJ, and the
relative order is significant, but there's a distinction between vertical
and horizontal stacking.

CGJ is also used in cases where there's an enclosing diacritic and another
one: should that diacritic be inside or outside the enclosing diacritic?
(we have examples in mathematical notations with diacritics liek arrows)

The case of CGJ used immediately after a base letter (or after a combining
character with combining class 0) encodes either a variant of the base
letter, or of the diacritic after CGJ.

The only case where CGJ is currently not used is at end of streams ; or
just before a base letter (but there could be applications for tricky cases
in Indic scripts) where ZWJ and ZWNJ are prefered (to control ligatures and
contextual letter forms such as subjoined letters).
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