'Much better if you let us know the source of this problem. Is this an exercise from some book / online course?” The source is just me exploring. I first looked at data C a = C a deriving (Show) and made Monad, Applicative, Monoid and Functors for it. So then tried Pair a = P (a, a) and stuck on Monad. Thanks Mike
On 18 Nov 2015, at 07:23, Kim-Ee Yeoh <ky3@atamo.com <mailto:ky3@atamo.com>> wrote:
On Wed, Nov 18, 2015 at 4:41 AM, Mike Houghton <mike_k_houghton@yahoo.co.uk <mailto:mike_k_houghton@yahoo.co.uk>> wrote:
And really return x = P (x, x) doesn’t seem correct anyway.
But if you look at the type, which is essentially "a -> (a,a)" there's only one way to write it, for the same reason that there's only one "a -> a" function.
Would someone please write the Monad with an explanation?
Much better if you let us know the source of this problem. Is this an exercise from some book / online course?
-- Kim-Ee _______________________________________________ Beginners mailing list Beginners@haskell.org <mailto:Beginners@haskell.org> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners