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{-# LANGUAGE MultiParamTypeClasses, KindSignatures, FlexibleInstances, DataKinds, PolyKinds, RankNTypes, AllowAmbiguousTypes, TypeOperators, TypeFamilies, ScopedTypeVariables #-}
{-# OPTIONS_GHC -fplugin DefaultLifted -fwarn-type-defaults #-}
-- Tests defaulting plugins
module Main where
import GHC.TypeLits
import Data.Proxy
import DefaultLifted
instance DefaultType Nat 4
instance DefaultType Nat 2
instance DefaultType Nat 0
class MyClass (a :: Nat) (b :: Nat) where
mc :: (KnownNat a, KnownNat b) => Proxy a -> Proxy b -> Integer
instance MyClass a b where
mc a b = natVal a + natVal b
q :: forall (a :: Nat). (KnownNat a) => Integer
q = natVal (Proxy :: Proxy a)
w :: forall (a :: Nat). (KnownNat a, 2 <= a) => Integer
w = natVal (Proxy :: Proxy a)
main :: IO ()
main = do
print $ q + w
print $ mc Proxy Proxy
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