traverse example fails

[sinistral]

The examples for cats.core/traverse throw "missing protocol method" exceptions in both Clojure (1.8.0) and ClojureScript (1.9.293). Using the example from the API documentation:

boot.user> (require '[cats.context :as ctx]
                    '[cats.core :as m]                    
                    '[cats.monad.maybe :as maybe])
;; => nil
boot.user> (defn inc-if-even
             [n]
             (if (even? n)
               (maybe/just (inc n))
               (maybe/nothing)))
;; => #'boot.user/inc-if-even
boot.user> (ctx/with-context maybe/context
             (m/traverse inc-if-even [2 4]))
java.lang.IllegalArgumentException: No implementation of method: :-get-context of protocol: #'cats.protocols/Contextual found for class: clojure.lang.PersistentVector

[sinistral]

I have just discovered that I was missing the necessary (require '[cats.builtin]). I am terribly sorry for the noise.

cljs.user> (require '[cats.builtin])
;; => true
cljs.user> (require '[cats.context :as ctx]
                    '[cats.core :as m]                    
                    '[cats.monad.maybe :as maybe])
;; => nil
cljs.user> (defn inc-if-even
             [n]
             (if (even? n)
               (maybe/just (inc n))
               (maybe/nothing)))
;; => #'cljs.user/inc-if-even
cljs.user> (ctx/with-context maybe/context
             (m/traverse inc-if-even '(2 4)))
;; => #<Just (3 5)>
cljs.user> (ctx/with-context maybe/context
             (m/traverse inc-if-even '(2 4 5)))
;; => #<Nothing>
cljs.user>