macro-utils: new macro deftemplate

1 files changed, 13 insertions, 1 deletions

diff --git a/src/clojure/contrib/macro_utils.clj b/src/clojure/contrib/macro_utils.clj
index 191f07f7..a243a5f9 100644
--- a/src/clojure/contrib/macro_utils.clj
+++ b/src/clojure/contrib/macro_utils.clj
@@ -1,7 +1,7 @@
 ;; Macrolet and symbol-macrolet
 
 ;; by Konrad Hinsen
-;; last updated May 5, 2009
+;; last updated May 25, 2009
 
 ;; Copyright (c) Konrad Hinsen, 2009. All rights reserved.  The use
 ;; and distribution terms for this software are covered by the Eclipse
@@ -211,6 +211,18 @@
   [& exprs]
   `(do ~@(doall (map expand-all exprs))))
 
+(defmacro deftemplate
+  "Define a macro that expands into forms after replacing the
+   symbols in params (a vector) by the corresponding parameters
+   given in the macro call."
+  [name params & forms]
+  (let [param-map (for [p params] (list (list 'quote p) (gensym)))
+	template-params (vec (map second param-map))
+	param-map (vec (apply concat param-map))
+	expansion (list 'list (list 'quote `symbol-macrolet) param-map
+			(list 'quote (cons 'do forms)))]
+    `(defmacro ~name ~template-params ~expansion)))
+
 (defn mexpand-1
   "Like clojure.core/macroexpand-1, but takes into account symbol macros."
   [form]