Michael Everson <[EMAIL PROTECTED]> wrote: > The Private Use Area is not to be classified. Anyone anywhere can use > any of its code points for anything.
Furthermore, even if William's scheme is intended to be a semi-private "convention" rather than an official part of Unicode -- much like Michael's (and John Cowan's) own ConScript Unicode Registry -- it seems unlikely that an elaborate indexing scheme such as the one William proposes would gain much of a following. Vendors have only recently started to implement surrogates properly, and still balk at decoding SCSU (which is easy; it's the encoding part that gets complex). And these official Unicode mechanisms are simple compared to William's "hex point" indexing scheme. Additionally, it is VERY important to repeat -- probably more important than anything else in this discussion -- that there is no automatic path to "promotion" of any private-use character to full Unicode status. Every character and script that is encoded in Unicode must undergo the same scrutiny, regardless of how (or whether) it may have been encoded in the past. That goes for Deseret and Shavian (accepted) as well as Klingon and Aiha (not accepted), all of which were encoded in ConScript but none of which were automatically "promoted" on that basis alone. There are two full Private Use planes, 131,068 code points in all (not counting the four noncharacters), certainly enough for any private-use implementation that would be envisioned as benefiting from William's proposal, and a lot easier to implement (and thus more likely to be used). My suggestion to William is that if he envisions a potentially widespread use for the PUA, he may consider creating a ConScript-like registry for the upper planes. That would be just as effective and much simpler. Apart from font vendors who use the PUA for presentation forms within the font, what current practices exist for using the PUA? I mentioned ConScript; how popular is its use? Are there any other commonly used practices or conventions? Apple has blocked out a code point for APPLE SIGN, and somebody (sorry, don't remember the name) mentioned a Microsoft convention of a subarea for symbols or dingbats. Maybe a discussion along these lines can reveal the true nature of PUA use and help William redirect his considerable energy toward a more practical system. -Doug Ewell Fullerton, California
