gistfile1.hs

  7 main :: IO()
  6 main = do
  5 
  4     forM [1000000..5000000] $ \x -> do
  3         a <- getCPUTime
  2         return $! fib x
  1         b <- getCPUTime
  0         putStrLn $ show ((b-a) `div` 10^9)

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[1 of 1] Compiling Main             ( higher-order-functions.hs, higher-order-functions.o )

higher-order-functions.hs:59:5:
    Couldn't match expected type `()' with actual type `[()]'
    Expected type: IO ()
      Actual type: IO [()]
    In a stmt of a 'do' block:
      forM [1000000 .. 5000000]
      $ \ x
          -> do { a <- getCPUTime;
                  return $! fib x;
                  .... }
    In the expression:
      do { forM [1000000 .. 5000000] $ \ x -> do { ... } }

shell returned 1

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