[Haskell-cafe] random question

Michael Mossey mpm at alumni.caltech.edu
Wed Oct 7 16:59:00 EDT 2009

My thread about randomness got hijacked so I need to restate my remaining 
question here. Is it acceptable to write pure routines that use but do not 
return generators, and then call several of them from an IO monad with a 
generator obtained by several calls to newStdGen?

shuffle :: RandomGen g => g -> [a] -> [a]
shuffle = ...

foo :: [a] -> [a] -> IO ()
foo xs ys = do
   g1 <- newStdGen
   print $ shuffle g1 xs
   g2 <- newStdGen
   print $ shuffle g2 ys

Does this kind of thing exhibit good pseudorandomness?


More information about the Haskell-Cafe mailing list