Is there a technical reason to avoid `$` in symbol names?

Question

This original version of this post asked about the pipe symbol as well the dollar sign, but there is an answer concerning the pipe symbol here: https://ask.clojure.org/index.php/11627/the-pipe-char-considered-valid-symbol-constituent-character

However, I'm still wondering about the dollar sign, $, which is not explicitly listed as a legal character for symbol names:
https://clojure.org/reference/reader#_symbols
In practice it can be used in symbols:
(def $ 42) $ ;==> 42 (defn a$b [a b] (or a b)) (a$b nil 'foo) ;==> foo
Putting aside the question of whether it's stylistically or pragmatically appropriate (e.g. because of worry about confusing others) to use $ in symbol names (e.g. because of worry about confusing others), is there a technical reason to avoid it?

For example, are there edge cases where using $ in a symbol would cause trouble? Or is it possible that in the future Clojure would use $ as special syntax?

(I have in fact used $ in symbol names in the past.)

Answer 1

$ is used in a lot of places (like Datomic) and I don't expect that to be problematic in the future.

Comments

I guess the one place it's potentially confusing is that it is used in symbols naming classes to separate outer and nested classes. Which I guess argues that it is pervasive in symbols, but has meaning in some contexts, but those contexts are probably disjoint from your needs.

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Thanks very much.  This is all good to know and very helpful.   (Yes, that case won't interfere with my intended and past uses.)