{- Copyright (C) 2011 Dr. Alistair Ward This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. -} {- | [@AUTHOR@] Dr. Alistair Ward [@DESCRIPTION@] Determines the CPU-time, required to evaluate the specified IO-action. -} module ToolShed.System.TimeAction( -- * Functions getCPUSeconds, printCPUSeconds ) where import qualified System.CPUTime import qualified System.IO -- | Time the specified IO-action, returning the required number of CPU-seconds and the result, as a 'Pair'. getCPUSeconds :: Fractional seconds => IO result -> IO (seconds, result) getCPUSeconds action = do startTime <- System.CPUTime.getCPUTime result <- action endTime <- System.CPUTime.getCPUTime return {-to IO-monad-} (fromInteger (endTime - startTime) / 1e12 {-convert from pico-seconds-}, result) -- | Print the time required by the specified IO-action. printCPUSeconds :: IO result -> IO result printCPUSeconds action = do (cpuSeconds, result) <- getCPUSeconds action System.IO.hPutStrLn System.IO.stderr $ "CPU-seconds:\t" ++ show (cpuSeconds :: Double) return {-to IO-monad-} result