Test whether a list contains a specific value in Clojure

Question

What is the best way to test whether a list contains a given value in Clojure?

In particular, the behaviour of contains? is currently confusing me:

Answer 1

Here's my standard util for the same purpose:

(defn in? 
  "true if coll contains elm"
  [coll elm]  
  (some #(= elm %) coll))