Thanks. Do you have a need today for more than 1 million codepoints for some reason? Or you are just predicting that we collectively will eventually? Or you just miss the theoretical elegance? Or what?
Only 137,000 of the 1 million Unicode points are categorized as Private Use, and the library I wrote addresses the need for more private use codepoints. A suggested path for people needing private use codepoints is:
* Use the 6400 codepoints in the BMP
* Begin using plane 0xF beginning at U+F0000
* After using the 32,000 codepoints in the bottom half of 0xF up to U+F7FFF, if you're certain you won't need more than 137,000 codepoints, continue using plane 0xF from U+F8000 onwards
* Otherwise, skip the top half of plane 0xF, and go straight to plane 0x10 beginning at U+100000, and start using the surrogates when you get to U+110000
As for needing more than a million codepoints, I've been looking at whether it's possible to represent CJK Unihan characters compositionally in the 6-byte codepoints (U+4000000 to U+7FFFFFFF) in the same way Korean Hangul has been represented since Unicode 2.0, thus creating many more Unihan characters that don't presently exist. Perhaps there'll be a demand for them one day!
