Superscript and Subscript Characters in General Use

[Richard Wordingham]

On Wed, 4 Jan 2017 13:43:50 +0100
Philippe Verdy <verdy_p at wanadoo.fr> wrote:

> Note that in French the right single quote is normally not used at
> all as a quotation mark, and when it appears between two letters it
> is unambiguously an apostrophe. I think the letter apostrophe was
> addede later in Unicode only for English to allow distrinctions. But
> I've rarely seen used. Later it was used as a substitute for a
> glottal stop in some Polynesian/Melanesian languages but the actual
> character was encoded and is preferable (its glyph is distinctive).

As consonants, what we have are spacing clones (U+02BC and U+02BE) of
the smooth breathing, usually used for glottal stops, and spacing
clones of the rough breathing (U+02BD and U+02BF).  We also have the
modifier modifications of the IPA letters U+02C0 and U+02C1. These
usages only fit English well when representing the glottalisation (or
even total loss) of /t/ after vowels.  
 
> 2017-01-04 12:44 GMT+01:00 John W Kennedy <john.w.kennedy at gmail.com>:
> 
> > No it isn’t. It isn’t an apostrophe; it’s a left single quote,
> > although some modern printers mistakenly suppose it to be an
> > apostrophe, and substitute one. And it isn’t an elision; it’s meant
> > as a substitute glyph for a superscript c.

For which I would suggest U+02BF MODIFIER LETTER LEFT HALF RING would
be the best modern representative of the substitute character!

Of course, that would further increase confusion of those who initially
read U+02BF as a superscript 'c', and only later, if ever, realise that
it's actually a rough breathing carefully distinguished from the
similar punctuation marks.

Richard.