Clojure Protocol Implementation not Found for Record Type in other namespace -

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we having few issues records , protocols in different namespaces.

we have protocol in namespace foo.proto.

(ns foo.proto)  (defprotocol proto    (do-stuff [this x y]))

i have record recorda in namespace foo.record:

(ns foo.record   (:require [foo.proto :as proto]))  (defrecord recorda [bar])  ;; recorda implements protocol:  (extend-type recorda     proto/proto     (do-stuff [this x y] (* x y (:bar this))))

this works fine long in repl. if on otherhand make uberjar , run code get:

no implementation of method: :do-stuff of protocol: #'foo.proto/proto found class

if on other hand implement protocol in type declaration so:

(defrecord recorda [bar]     proto/proto     (do-stuff [this x y] (* x y (:bar this))))

we no longer error (which took time figure out). if move declaration of proto same ns recorda not error either.

my questions:

  1. what difference between implementing in declaration , in extend-type or extend-protocol?

  2. why work if move record , protocol declarations same ns?

thanks

the issue may in how including record , protocol within file using them. following works me:

record.clj

(ns testclojure.record   (:require [testclojure.proto :as proto]))  (defrecord recorda [bar])  (extend-type recorda   proto/proto   (do-stuff [this x y] (* x y (:bar this))))

proto.clj

(ns testclojure.proto)  (defprotocol proto   (do-stuff [this x y]))

core.clj

(ns testclojure.core   (:require [testclojure.record :refer [->recorda]]             [testclojure.proto :refer :all])   (:gen-class))  (defn -main [& args]   (-> (->recorda 2)       (do-stuff 2 6)       (println)))

after lein uberjar , running jar directly, correct answer of 24.

as why works different combinations of namespaces , extending, defrecord creates java class while extend-type creates entry in :impls collection of protocol.


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