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diff --git a/modules/monads/src/test/clojure/clojure/contrib/test_monads.clj b/modules/monads/src/test/clojure/clojure/contrib/test_monads.clj
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+++ b/modules/monads/src/test/clojure/clojure/contrib/test_monads.clj
@@ -0,0 +1,78 @@
+;; Test routines for monads.clj
+
+;; by Konrad Hinsen
+;; last updated March 28, 2009
+
+;; Copyright (c) Konrad Hinsen, 2008. All rights reserved.  The use
+;; and distribution terms for this software are covered by the Eclipse
+;; Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+;; which can be found in the file epl-v10.html 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.
+
+(ns clojure.contrib.test-monads
+  (:use [clojure.test :only (deftest is are run-tests)]
+	[clojure.contrib.monads
+	 :only (with-monad domonad m-lift m-seq m-chain
+		sequence-m maybe-m state-m maybe-t sequence-t)]))
+
+(deftest sequence-monad
+  (with-monad sequence-m
+    (are [a b] (= a b)
+      (domonad [x (range 3) y (range 2)] (+ x y))
+        '(0 1 1 2 2 3)
+      (domonad [x (range 5) y (range (+ 1 x)) :when  (= (+ x y) 2)] (list x y))
+        '((1 1) (2 0))
+      ((m-lift 2 #(list %1 %2)) (range 3) (range 2))
+        '((0 0) (0 1) (1 0) (1 1) (2 0) (2 1))
+      (m-seq (replicate 3 (range 2)))
+        '((0 0 0) (0 0 1) (0 1 0) (0 1 1) (1 0 0) (1 0 1) (1 1 0) (1 1 1))
+      ((m-chain (replicate 3 range)) 5)
+        '(0 0 0 1 0 0 1 0 1 2)
+      (m-plus (range 3) (range 2))
+        '(0 1 2 0 1))))
+
+(deftest maybe-monad
+  (with-monad maybe-m
+    (let [m+ (m-lift 2 +)
+          mdiv (fn [x y] (domonad [a x  b y  :when (not (zero? b))] (/ a b)))]
+      (are [a b] (= a b)
+        (m+ (m-result 1) (m-result 3))
+	  (m-result 4)
+        (mdiv (m-result 1) (m-result 3))
+	  (m-result (/ 1 3))
+        (m+ 1 (mdiv (m-result 1) (m-result 0)))
+	  m-zero
+	(m-plus m-zero (m-result 1) m-zero (m-result 2))
+	  (m-result 1)))))
+
+(deftest seq-maybe-monad
+  (with-monad (maybe-t sequence-m)
+    (letfn [(pairs [xs] ((m-lift 2 #(list %1 %2)) xs xs))]
+      (are [a b] (= a b)
+        ((m-lift 1 inc) (for [n (range 10)] (when (odd? n) n)))
+          '(nil 2 nil 4 nil 6 nil 8 nil 10)
+        (pairs (for [n (range 5)] (when (odd? n) n)))
+          '(nil nil (1 1) nil (1 3) nil nil nil (3 1) nil (3 3) nil nil)))))
+
+(deftest state-maybe-monad
+  (with-monad (maybe-t state-m)
+    (is (= (for [[a b c d] (list [1 2 3 4] [nil 2 3 4] [ 1 nil 3 4]
+				 [nil nil 3 4] [1 2 nil nil])]
+	     (let [f (domonad
+		       [x (m-plus (m-result a) (m-result b))
+			y (m-plus (m-result c) (m-result d))]
+		       (+ x y))]
+	       (f :state)))
+	   (list [4 :state] [5 :state] [4 :state] [nil :state] [nil :state])))))
+
+(deftest state-seq-monad
+  (with-monad (sequence-t state-m)
+    (is (= (let [[a b c d] [1 2 10 20]
+		 f (domonad
+		     [x (m-plus (m-result a) (m-result b))
+		      y (m-plus (m-result c) (m-result d))]
+		     (+ x y))]
+	     (f :state)))
+	(list [(list 11 21 12 22) :state]))))