Make memfn allow for type-hinting the method receiver.

Signed-off-by: Stuart Halloway <[email protected]>

Author: tsdh

src/clj/clojure/core.clj

@@ -3447,11 +3447,14 @@
   "Expands into code that creates a fn that expects to be passed an
   object and any args and calls the named instance method on the
   object passing the args. Use when you want to treat a Java method as
-  a first-class fn."
+  a first-class fn. name may be type-hinted with the method receiver's
+  type in order to avoid reflective calls."
   {:added "1.0"}
   [name & args]
-  `(fn [target# ~@args]
-     (. target# (~name ~@args))))
+  (let [t (with-meta (gensym "target")
+            (meta name))]
+    `(fn [~t ~@args]
+       (. ~t (~name ~@args)))))
 
 (defmacro time
   "Evaluates expr and prints the time it took.  Returns the value of