monads explained via clojure spec.

monads explained via clojure spec

(def my-inc inc)
(def my-dec dec)

(s/fdef my-inc
  :args (s/cat :x int?)
  :fn #(= (inc (-> % :args :x ))
         (-> % :ret))
  :ret int?)

(s/fdef my-dec
  :args (s/cat :x int?)
  :fn #(= (dec (-> % :args :x ))
         (-> % :ret))
  :ret int?)


(s/fdef monoid
  :args (and
          (s/cat :some-fn my-inc :some-other-fn my-dec)
          (= (s/args my-inc) (s/args my-dec))
          (= (s/ret my-inc) (s/ret my-dec)))
  :ret (s/comp my-inc my-dec))
  

i meant monad in the fdef!