Clojure get map key by value

Question

I\'m a new clojure programmer.

Given...

{:foo \"bar\"}

Is there a way to retrieve the name of the key with a value \"bar\"?

Answer 1

user> (->> {:a "bar" :b "foo" :c "bar" :d "baz"} ; initial map
           (group-by val)   ; sorted into a new map based on value of each key
           (#(get % "bar")) ; extract the entries that had value "bar"
           (map key))     ; get the keys that had value bar
(:a :c)