One of the ideas lurking in my head was a symbol to close all open parenthesis
For example, assuming [] isn't used for anything:
(def fun (args) (a (b (c (d)))))
(def fun (args) (a (b (c (d))]
Granted, something like (a (b (c (d] looks a bit odd, but this looks less odd:
(a (b (c (d (e (f (g (h)))]
(a (b (c (d (x y) (z (e (f (g (h)))]
I shy away from it only 'cause it reduces the number of editors which can make sense of the brackets.
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