I'm returning to Clojure in earnest for the first time since 1.1 (and very happy to be back!). Apologies if this question revisits old issues.
I'm trying to understand why the semantics of protocols are such that the third statement here returns true: user=> (defprotocol Bashable (bash [this]) (boom [this])) Bashable user=> (defrecord Record [] Bashable (bash [this] "bash!")) user.Record user=> (and (satisfies? Bashable (Record.)) (extends? Bashable Record)) true This returns true even though boom is not implemented for Record: user=> (boom (Record.)) AbstractMethodError user.Record.boom()Ljava/lang/Object; user/eval55 (NO_SOURCE_FILE:3) Apparently, types/records can implement a protocol "in name only." What is behind this choice? Intuitively, I would have conceived of a protocol as a collection of methods all of which must be implemented in order for a type/record to extend the protocol. A second question. How does one "explicitly" extend a protocol per the documentation of the extenders function? Intuitively, I would have thought that the code above "explicitly" extends Bashable if it extends Bashable at all. Yet: user=> (extenders Bashable) nil Thank you. All the best, Garth Sheldon-Coulson -- 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
