It may be reasonable for Michael to argue for the subscript a, e, and o for Indo-European, since he already got a subscript i and u encoded for the UPA. Arguably, the subscript a, e, and o *are* phonetic modifier letters, since they represent hypothesized vowel-coloring of the laryngeal symbol. The subscript x is trickier, since it is an algebraic substitution for (a ~ e ~ o), so we are skating on thin ice there, with a notation that is arguably not a phonetic modifier letter.
There are UPA "wildcard" characters used in analogous description of vowel harmony: U+1D3D for instance. Letter x is hardly different.
And the subscript / is over the edge, as far as I am concerned.
U+208D and U+208E aren't.
It clearly is introducing a generic notational convention into the realm where we are expecting only discrete modifier letters to require encoding as separate characters. And if I run into an Indo-Europeanist notation of
the alternations such as:
*h<sub>1/3</sub>
or
*dhug'hH(<sub>e/o</sub>)ter
what is to guarantee that I won't find alternative representations of such formulations using "~" instead of "/", for example? Do we then also need a subscript tilde to handle that?
We are not proposing to encode something which we have not encountered, and do not accept the burden of proof about what you will or will not find. That's not right, Ken. That's not how we have ever proceeded. People come with requirements and evidence. We don't throw that out because of what can be "imagined".
Furthermore, Michael carefully dodged the point that all of these Indo-European sources are *already* fonted, styled text. They are *not* plain text, but mix italic citations with Roman forms. Unless we are going to also head down the road of plain text italic letter clones for Indo-European, all of this material already has to be dealt with as rich text.
The run of the citations are italicized to set them off from the rest of the text. Same as with the UPA. This is not the same thing as saying that what's within the citations isn't required for plain-text representation.
I concur that superscript h and w and so on are o.k. -- they truly are modifier letters and appropriate in transcriptional plain text. Nobody is arguing about that point.
Though they are also IPA characters, and you like the IPA. ;-)
But I think it is a mistake to be using the compatibility subscript digits for generic subscripting.
That's your preference.
Of course, I can't help it if people are already doing so, but it gets us into this conundrum of people expecting any subscripted expression to be expressible in plain text,
It depends on what is being expressed.
and that is just clearly wrong -- it isn't generic or scalable.
I don't know what you mean by either "generic" or "scalable".
And it results in people coming back to the table asking for more of them every time some community is found making some other use of them.
Golly, Ken, that's been going on with phonetic characters for a while now. That's part of the work we're involved with.
--
Michael Everson * * Everson Typography * * http://www.evertype.com
