Quasiquotation marks

[Frédéric Grosshans]

Le 10/06/2014 15:33, Leonardo Boiko a écrit :
> What about using U+0331 "combining macron below" or U+0320 "combining 
> minus below"?
That would more similar to the underline hack discussed briefly here :
http://fanac.org/Fannish_Reference_Works/Fan_terms/Fan_terms-07.html

But I think it’s the wrong character : typewriters had the underscore 
(_) charcater, which was used to underline, and which was sometimes used 
as a "combining macron below". But this was not the one chosen in the 
1940’s to create the quasiquote, but the hyphen. Using U+0335 COMBINING 
SHORT STROKE OVERLAY seems to closer to the original.

The various posts linked in that thread tell "̵ these quasiquotaion marks 
were practical but everyone says '̵They are difficult to use with modern 
word processors !'̵ "̵

Given the fact that it is possible to reproduce them with U+0335 
COMBINING SHORT STROKE OVERLAY, what is the practice about encoding them 
as a new character ? Would the case (given enough usage proof) be 
similar to the encoding of ɏ U+024F LATIN SMALL LETTER Y WITH STROKE, 
which, I guess, has probably a similar origin in overstruck typewriter’s 
characters ? Or the fact that the stroke doesn’t touch the quotes makes 
the situation closer to non-existing  precomposed latin character + 
diacritic combinations 
(http://www.unicode.org/faq/char_combmark.html#13) , and a specific 
symbol would be against NFC stability and un-encodeable ?