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diff --git a/testsuite/tests/lib/should_run/memo002.hs b/testsuite/tests/lib/should_run/memo002.hs
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+++ b/testsuite/tests/lib/should_run/memo002.hs
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+module Main where
+
+import Memo2              ( memo )
+import Data.List          ( genericLength, genericReplicate )
+import System.Environment ( getArgs )
+
+main :: IO ()
+main = do (arg:_) <- getArgs
+	  mapM_ printTriple [ (i,fib i,mfib i) | i <- [10..read arg] ]
+  where printTriple (i,fi,mfi) = do print i
+				    print fi
+				    print mfi
+				    putStrLn ""
+
+-- There is not much point in memoising Integers, so we use unary "numbers" instead
+mfib :: Integer -> Integer
+mfib = genericLength . mfib' . flip genericReplicate ()
+
+mfib' :: [()] -> [()]
+mfib' = memo ufib
+
+ufib :: [()] -> [()]
+ufib []              = [()]
+ufib [()]            = [()]
+ufib (():n1@(():n2)) = mfib' n1 ++ mfib' n2
+
+fib :: Integer -> Integer
+fib 0 = 1
+fib 1 = 1
+fib n = fib (n-1) + fib (n-2)