Clojure - default protocol implementation on Object fails?

clojure, protocols

Solution

Instead of

(deftype NewsItem
  [text date]
  Saving)

Just use:

(deftype NewsItem
  [text date])

Problem

I have created a simpe protocol and a type in Clojure: ``` (defprotocol Saving (save [this] "saves to mongodb")) ;default implementation (extend-type Object Saving (save [this] (encode this))) (deftype NewsItem [text date] Saving) ``` However, when I try: ``` => (def news-item (->NewsItem "Super News!!!" "today")) ``` and then: ``` => (save news-item) ``` I get: ``` AbstractMethodError luminous_test.models.model.NewsItem.save()Ljava/lang/Object; luminous-test.models.model/eval2450 (NO_SOURCE_FILE:1) ``` What am I doing wrong? I feel like following the lines of creating a default protocol implementation but that's what I am getting...

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