module Parallel (parMapM, parMapM_, parSequence) where

import Control.Concurrent.ParallelIO.Local (parallel, parallel_, withPool)
import GHC.Conc (getNumProcessors)

parMapM :: (a -> IO b) -> [a] -> IO [b]
parMapM f xs = do
  n <- getNumProcessors
  withPool n $ \pool -> parallel pool (map f xs)

parMapM_ :: (a -> IO ()) -> [a] -> IO ()
parMapM_ f xs = do
  n <- getNumProcessors
  withPool n $ \pool -> parallel_ pool (map f xs)

parSequence :: [IO a] -> IO [a]
parSequence xs = do
  n <- getNumProcessors
  withPool n $ \pool -> parallel pool xs