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{-|
Module : Verismith
Description : Verismith
Copyright : (c) 2020, Yann Herklotz
License : GPL-3
Maintainer : yann [at] yannherklotz [dot] com
Stability : experimental
Portability : POSIX
-}
module Verismith.Utils
(generateByteString)
where
import System.Random (mkStdGen, newStdGen, randoms)
import Data.ByteString (ByteString, pack)
generateByteString :: (Maybe Int) -> Int -> Int -> IO [ByteString]
generateByteString mseed size n = do
fmap pack . chunksOf size . take (size * n) . randoms <$>
case mseed of
Just seed' -> return $ mkStdGen seed'
Nothing -> newStdGen
where
chunksOf i _ | i <= 0 = error $ "chunksOf, number must be positive, got " ++ show i
chunksOf i xs = repeatedly (splitAt i) xs
repeatedly _ [] = []
repeatedly f as = b : repeatedly f as'
where (b, as') = f as
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