cond collection type with tests

gistfile1.clj

(defn collection-type [col]
  (cond (set? col) :set
        (map? col) :map
        (list? col) :list
        (vector? col) :vector
        (seq? col) :seq))

(deftest collection-type-returns-correct-name
  (is (= :list (collection-type '())))
  (is (= :map (collection-type {})))
  (is (= :vector (collection-type [])))
  (is (= :set (collection-type #{}))))