[Haskell-cafe] What's the problem with iota's type signature?

[David Leimbach]

On Wed, May 27, 2009 at 7:33 PM, michael rice <nowgate at yahoo.com> 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]


Int is not a class, and you are using it as such?



>
>
> --usage: [3,4,5] >>= iota
> --should produce [1,2,3,1,2,3,4,1,2,3,4,5]
>
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