preliminary proposal: New Unicode characters for Arabic music half-flat and half-sharp symbols

[Hans Åberg via Unicode]

> On 16 May 2018, at 09:42, Hans Åberg via Unicode <unicode at unicode.org> wrote:
> 
>> On 16 May 2018, at 00:48, Ken Whistler via Unicode <unicode at unicode.org> wrote:
>> 
>>> A proposal should also show evidence of usage and glyph variations.
>> 
>> And should probably refer to the relationship between these signs and the existing:
> 
> It would be best to encode the SMuFL symbols, which is rather comprehensive and include those:
> https://www.smufl.org
> http://www.smufl.org/version/latest/
> 
>> U+1D132 MUSICAL SYMBOL QUARTER TONE SHARP
>> U+1D133 MUSICAL SYMBOL QUARTER TONE FLAT
>> 
>> which are also half-sharp or half-flat accidentals.
>> 
>> The wiki on flat signs shows this flat with a crossbar, as well as a reversed flat symbol, to represent the half-flat.
>> 
>> And the wiki on sharp signs shows this sharp minus one vertical bar to represent the half-sharp.
>> 
>> So there may be some use of these signs in microtonal notation, outside of an Arabic context, as well. See:
>> 
>> https://en.wikipedia.org/wiki/Accidental_(music)#Microtonal_notation
> 
> These are otherwise originally the same, but has since drifted. So whether to unify them or having them separate might be best to see what SMuFL does, as they are experts on the issue.

Clarification: The Arabic accidentals, listed here as separate entities
  http://www.smufl.org/version/latest/range/arabicAccidentals/
appear in LilyPond as ordinary microtonal accidentals:
  http://lilypond.org/doc/v2.18/Documentation/notation/the-feta-font#accidental-glyphs

So what I meant above is that originally, they were the same, i.e., when starting to use them in Arabic music, one took some Western microtonal accidentals. Now they mean microtones in the style of Arabic music, and the musical interpretation varies.