{-# LANGUAGE GeneralizedNewtypeDeriving , UndecidableInstances , FlexibleContexts , GADTs , DerivingStrategies , CPP #-} module Test.Universum.Issue208 () where #if __GLASGOW_HASKELL__ >= 900 import Universum (Container) -- In ghc-8.6.3 this code will produce a @redundant constraint@ warning. -- In ghc-9.0.2 and newer no warnings would be produced. -- Issue #208: https://github.com/serokell/universum/issues/208 newtype Test = Test [Int] deriving newtype (Container) #endif