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Higher-rank type families #28

Open goldfirere opened 9 years ago

goldfirere commented 9 years ago

This should probably work (!):

{-# LANGUAGE TypeFamilies, PolyKinds, DataKinds, TypeOperators #-}

import Data.Type.Equality

type family GCastWith (eq :: a :~: b) (x :: (a ~ b) => r) :: r where
  GCastWith 'Refl x = x