haskell,random , Haskell - generate and use the same random list

Haskell - generate and use the same random list


Tag: haskell,random

In Haskell, I'd like to generate a random list of Ints and use it throughout my program. My current solution causes the array to be created randomly each time I access/use it.

How can I overcome this problem?


Here is a simple example (@luqui mentioned) you should be able to generalize to your need:

module Main where

import Control.Monad (replicateM)
import System.Random (randomRIO)

main :: IO ()
main = do
  randomList <- randomInts 10 (1,6)
  print randomList
  let s = myFunUsingRandomList randomList
  print s

myFunUsingRandomList :: [Int] -> Int
myFunUsingRandomList list = sum list

randomInts :: Int -> (Int,Int) -> IO [Int]
randomInts len bounds = replicateM len $ randomRIO bounds



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