(let [ truthys (filter #(filter-func %) coll)
falsys (filter #(not filter-func %) coll)]
This code traverves coll twice and applys filter-func twice to each element. I was wondering, is there a way to filter coll into both truthys and falsys in just one go?
(let [{truhys true, falsys false}
(group-by filter-func coll)]
...)