Type

(all (K V) (-> (hash-t K V) (hash-t V (set-t K))))

Description

Swap keys and values, grouping duplicate values into a set of keys.

Examples

(hash-invert-group (@hash 1 2 3 4 2 2 4 4))
;; => (@hash 2 (@set 1 2) 4 (@set 3 4))