I'm revisiting a browser plugin I created a while ago that provides conversion to and from various Unicode escape sequences.
However, I have now absentmindedly forgotten, and have been unable to rediscover, that mentions of languages where escape sequences like\C{Latin Small Letter A}
are supposed to work (Unicode descriptions) are actually Unicode character replacement, in this case "a").
I believe it is written in PHP, or at least a proposal for PHP, but I don't see any spec supporting this syntax right now.
PHP can only use code points
Python can
You can use a Python script and call it from PHP