@@ -1,3 +1,4 @@
1+{-# LANGUAGE CPP #-}
12{-# LANGUAGE GeneralizedNewtypeDeriving #-}
23{-# LANGUAGE LambdaCase #-}
34{-# LANGUAGE PolyKinds #-}
@@ -20,7 +21,9 @@ import Data.Functor.Misc
2021import qualified Data.IntMap as IntMap
2122import qualified Data.Map as Map
2223import Data.Monoid.DecidablyEmpty
24+#if !MIN_VERSION_base(4,11,0)
2325import Data.Semigroup (Semigroup (..))
26+#endif
2427import Data.Some (Some)
2528
2629-- | A set of changes to a 'DMap'. Any element may be inserted/updated or deleted.