In Clojure, hash maps are functions of their keys. If you use keywords as keys, then keywords are also functions of maps. ({:a 1} :a) => 1 (:a {:a

In Clojure, hash maps are functions of their keys. If you use keywords as keys, then keywords are also functions of maps. ({:a 1} :a) => 1 (:a {:a 1}) => 1 (map {2 4} [1 2 3]) => (nil 4 nil) (map {:a 1 :b 2 :c 3} [:a :b :c]) => (1 2 3)