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+;;; enum.clj -- Java enum classes in Clojure
+
+;; by Stuart Sierra, http://www.stuartsierra.com/
+;; May 29, 2008
+
+;; Copyright (c) 2008 Stuart Sierra. All rights reserved.  The use and
+;; distribution terms for this software are covered by the Common
+;; Public License 1.0 (http://www.opensource.org/licenses/cpl1.0.php)
+;; which can be found in the file CPL.TXT at the root of this
+;; distribution.  By using this software in any fashion, you are
+;; agreeing to be bound by the terms of this license.  You must not
+;; remove this notice, or any other, from this software.
+
+
+;; This file helps define Java Enums, introduced in Java 1.5.  Use it
+;; when you need to define an enum to pass to a Java method.
+;;
+;; This file depends on genclass.clj in the Clojure distribution.
+
+
+(clojure/in-ns 'clojure.contrib.enum)
+(clojure/refer 'clojure)
+
+(defmacro defenum
+  "Generates and loads a subclass of java.lang.Enum, then
+  defs symbols as enumerated instances of that class.
+
+  Example:  (defenum my.package.MyEnum FOO BAR)
+            ;; FOO and BAR are now instances of MyEnum
+
+  Java equivalent:  enum MyEnum { FOO, BAR };
+
+  Caveats:
+  1. The generated class has no values() method.  
+  2. The generated class returns false for Class.isEnum().
+  3. Enum.valueOf(Class, String) will not work.
+  4. Redefining an enum is allowed, but enumeration resets
+     to zero."
+  [class & symbols]
+  ;; Can't load a class twice, so check first:
+  (try (. Class (forName (str class)))  
+       (catch java.lang.ClassNotFoundException e
+         (gen-and-load-class (str class) :extends java.lang.Enum)))
+  (cons 'do
+        (map (fn [sym val]
+                 `(def ~sym (new ~class ~(str sym) ~val)))
+             symbols (iterate inc 0))))