On 3/5/2012 12:17 PM, Benjamin M Scarborough wrote:
On Mon, Mar 5, 2012 at 19:09, Michael Everson wrote:
No, because both the combining-a and the combining-diaeresis are bound to the
base letter; the combining diaeresis is not bound to the combining-a.
Just like the proposed U+1ABB COMBINING PARENTHESIS ABOVE will be bound to the
base letter, not the combining mark that it's parenthesizing. Oops.
—Ben Scarborough
That's not an "oops". It is intentional. Michael's wording is
misleading, because combining
marks in any case are not "bound" to base letters. The standard goes to
some length
to provide terminology for this. See D61a Dependence and D61b Graphical
application,
in Chapter 3 of the standard.
Neither of those concepts prevents (or requires) the interpretation of
sequences of
combining marks as having strict *semantic* binding in any one
particular way.
That is important, not only for cases like the German dialectological
parentheses,
which are handled most efficiently (and intuitively) in the way proposed
for their
encoding, but also for much more widespread cases where a combining mark
may be applied a single character, but where the intent of the modification
applies notionally, semantically, or phonologically to entities larger
than that single
character. The most obvious case of this is tone marking in
transliteration, where
a vocalic nucleus may be represented by a sequence of letters, but the
tone mark
is graphically "applied" to just one of them.
--Ken
