testsuite/tests/simplCore/should_compile/OpaqueNoCastWW.hs


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{-# LANGUAGE DataKinds #-}
{-# OPTIONS_GHC -O0 #-}
module OpaqueNoCastWW where

import GHC.TypeNats

newtype Signed (n :: Nat) = S { unsafeToInteger :: Integer}

-- Normally introduces a worker of type: Signed m -> Signed n -> Integer
times :: Signed m -> Signed n -> Signed (m + n)
times (S a) (S b) = S (a * b)
{-# OPAQUE times #-}