On 28/05/2009 04:33, michael rice wrote:
Still exploring monads. I don't understand why the type signature for
double is OK, but not the one for iota.
Michael
=================
--double :: (Int a) => a -> Maybe b
--double x = Just (x + x)
iota :: (Int a) => a -> [b]
iota n = [1..n]
--usage: [3,4,5] >>= iota
--should produce [1,2,3,1,2,3,4,1,2,3,4,5]
iota is executed within the monad and as such must respect its law ?
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