I started using private class fields, as described
here (a stage 3 proposal that is widely implemented, though not actually standardized yet AFAICT).
These are normal fields that start with a hash.
I find in js--proper-indentation the line (annotated by git blame):
17b5d0f7077 (Chong Yidong 2009-08-14 2864) ((eq (char-after) ?#) 0)
It sets the indentation for a line starting with # unconditionally to 0. I cannot find any other use of # in JavaScript that would justify treating lines starting with # apparently like C preprocessor macros. There is other related code, and it all seems to go back to when js.el was first installed in Emacs.
Is this just because the code was originally based on cc-mode or something, and the references to hash were never removed? Or was cpp used with early JavaScript?? I see references such as js--opt-cpp-start which says "Regexp matching the prefix of a cpp directive", and a match for "#define" in js--update-quick-match-re.
I cannot see any code in js-tests.el that tests this cpp-related functionality.
Is there some reason to keep the cpp-related code in js.el? I presume removing it would simplify then adding support for private class fields; indeed, maybe no particular support is needed if cpp support is first removed.
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