The java version would look like: Class c = byte[].class; But since the clojure way to obtain a class is simply to use its name literal, e.g.: user=> (type String) java.lang.Class the only way to get the class of an array would involve either a function call or a change to the reader. And java doesn't make it easy since all array-class stuff, such as Class.isArray(), is native code. The best I've come up with is: user=> (defn #^Class array-class "Returns the Class of an array of component type c" [#^Class c] (when c (class (java.lang.reflect.Array/newInstance c 0)))) user=> (array-class String) [Ljava.lang.String; which appears faster than using Class/forName with a created string. But since one *can* type a literal byte array class in java, I'd imagine there's some way to implement this with bytecode magic, rather than going through java.lang.reflect.Array.
On Mar 24, 3:39 pm, Frank Siebenlist <frank.siebenl...@gmail.com> wrote: > Right - not very different from the (class (byte-array 1)) that I came up > with in the mean time... all not very clojuresque. > > -FS. > > On Mar 24, 2010, at 3:03 PM, ataggart wrote: > > > > > For type-hinting #^"[B" works, but for obtaining and passing the class > > to defmethod, the best I can come up with is (Class/forName "[B"). > > > On Mar 24, 11:02 am, Frank Siebenlist <frank.siebenl...@gmail.com> > > wrote: > >> The following repl session shows my attempt to dispatch a multimethod on > >> "type": > > >> ... > >> user> (defmulti mm type) > >> #'user/mm > >> user> (type "a") > >> java.lang.String > >> user> (defmethod mm java.lang.String [s] (println "string")) > >> #<MultiFn clojure.lang.mult...@41e3a0ec> > >> user> (mm "a") > >> string > >> nil > >> user> (type (.getBytes "a")) > >> [B > >> user> (defmethod mm [B [b] (println "bytes")) > >> ; Evaluation aborted. > >> user> (def ba-type (type (.getBytes "a"))) > >> #'user/ba-type > >> user> (defmethod mm ba-type [b] (println "bytes")) > >> #<MultiFn clojure.lang.mult...@41e3a0ec> > >> user> (mm (.getBytes "a")) > >> bytes > >> nil > >> user> > >> ... > > >> It works easily for the string, but for a native java byte array, type (or > >> class) gives me back this "[B", which I'm unable to use as a dispatch > >> value for the defmethod. > >> I can, however, assign the value to a reference and us that to dispatch on > >> successfully - but that feels like a hack. > > >> Is there a way to express the byte array type in a different way than "[B" > >> that would work? > > >> Thanks, Frank. > > > -- > > 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 > > > To unsubscribe from this group, send email to > > clojure+unsubscribegooglegroups.com or reply to this email with the words > > "REMOVE ME" as the subject. -- 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 To unsubscribe from this group, send email to clojure+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.
