On May 27, 1:10 am, Allen Johnson <akjohnso...@gmail.com> wrote: > Hey everyone. I was playing around with the protocols/deftype stuff > and ran into a weird NullPointerException when calling the satisfies? > function. Seems to only happen with a java.lang.Object instance. > > Clojure 1.2.0-master-SNAPSHOT > user=> (defprotocol Greeter (greet [this])) > Greeter > user=> (satisfies? Greeter nil) > false > user=> (satisfies? Greeter "") > false > user=> (satisfies? Greeter (Object.)) > java.lang.NullPointerException (NO_SOURCE_FILE:0) > > Narrowed it down to this function: > > ;; core_deftype.clj > (defn find-protocol-impl [protocolx] > (if (instance? (:on-interfaceprotocol) x) > x > (let [c (class x) > impl #(get (:implsprotocol) %)] > (or (impl c) > (and c (or (first (remove nil? (map impl (butlast (super-chain > c))))) > (when-let [t (reduce pref (filter impl (disj > (supers c) Object)))] > (impl t)) > (impl Object))))))) > > More specifically, here: > > (disj (supers c) Object) > > Since in this case, `c` is java.lang.Object, supers returns nil which > disj doesn't seem to like. Shouldn't disj handle nil gracefully? >
Yes, could you please enter a ticket for this? Thanks, Rich -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
