[Haskell-beginners] random

Brent Yorgey byorgey at seas.upenn.edu
Sat Oct 24 20:05:40 EDT 2009


On Sat, Oct 24, 2009 at 05:59:35PM +0100, John Moore wrote:
> Hi All,
>            Can anyone help me I want to produce a list of three random
> numbers for e.g. [7,8,1]
> I tried using x <- getStdRandom $ randomR (1,10) but don't really understand
> this and it only generates one number. Any help greatly appreciated.

replicateM is your friend:
  
  replicateM :: (Monad m) => Int -> m a -> m [a]

so if 'foo' produces a single random number, then 'replicateM 3 foo'
produces a list of three.

-Brent


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