chickadee » srfi-209 » enum-set-adjoin

Returns an enum set that contains the members of enum-set and the enums. It is an error if the members of the result do not all belong to the same enum type.

(define reddish+blue (enum-set-adjoin reddish color-blue))

(enum-set<? reddish reddish+blue) ⇒ #t
(enum-set-contains? reddish+blue color-blue) ⇒ #t