Hi John,
When I was first encountered replicateM I found it really hard to
understand. So,of course, I am audacious enough to assume that it is hard
for you too!
The code suggested by Brent , 'replicateM 3 foo' is a nicer way of writing
the following:
foo = do
x <- getStdRandom $ randomR (1,10)
y <- getStdRandom $ randomR (1,10)
z <- getStdRandom $ randomR (1,10)
return [x,y,z]
Hope this helped.
-deech
On Sat, Oct 24, 2009 at 7:05 PM, Brent Yorgey
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 _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners