On Thu, Apr 12, 2018 at 3:47 PM, Dennis Raddle <dennis.raddle@gmail.com> wrote:

myFunc :: a -> b -> c

myFunc x y z = ...

  where

    helper :: a -> [b]

    helper xx = ...

Notice that I'm attempting to declare 'helper' using my type variables. I've noticed that this results in an error.

Is this actually possible, and how?

You need the ScopedTypeVariables extension, *and* to "declare" the type variables whose scope is to be extended with an explicit "forall" in the signature.

--

brandon s allbery kf8nh                               sine nomine associates

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