Require base >= 4.11

There were multiple build failures with GHC-8.2 due
to (<>) and Semigroup not being in scope.

hnix.cabal

@@ -489,7 +489,7 @@ library
   build-depends:
       aeson >= 1.4.2 && < 1.5
     , array >=0.4 && <0.6
-    , base >=4.9 && <5
+    , base >=4.11 && <5
     , binary >= 0.8.5 && < 0.9
     , bytestring >= 0.10.8 && < 0.11
     , comonad >= 5.0.4 && < 5.1
@@ -644,7 +644,7 @@ test-suite hnix-tests
   build-depends:
       Diff
     , Glob
-    , base >=4.9 && <5
+    , base >=4.11 && <5
     , bytestring
     , containers
     , data-fix
@@ -705,7 +705,7 @@ benchmark hnix-benchmarks
       benchmarks
   ghc-options: -Wall
   build-depends:
-      base >=4.9 && <5
+      base >=4.11 && <5
     , bytestring
     , containers
     , criterion

src/Nix/Cache.hs

@@ -5,7 +5,7 @@ module Nix.Cache where
 import qualified Data.ByteString.Lazy          as BS
 import           Nix.Expr.Types.Annotated
 
-#if defined (__linux__) && MIN_VERSION_base(4, 10, 0)
+#if defined (__linux__)
 #define USE_COMPACT 1
 #endif
 

src/Nix/Expr/Types.hs

@@ -68,10 +68,8 @@ import           Nix.Utils
 import           Text.Megaparsec.Pos
 import           Text.Read.Deriving
 import           Text.Show.Deriving
-#if MIN_VERSION_base(4, 10, 0)
 import           Type.Reflection                ( eqTypeRep )
 import qualified Type.Reflection               as Reflection
-#endif
 
 type VarName = Text
 
@@ -83,14 +81,6 @@ hashAt = flip alterF
 instance Hashable1 NonEmpty
 #endif
 
-#if !MIN_VERSION_base(4, 10, 0)
-instance Eq1 NonEmpty where
-  liftEq eq (a NE.:| as) (b NE.:| bs) = eq a b && liftEq eq as bs
-instance Show1 NonEmpty where
-  liftShowsPrec shwP shwL p (a NE.:| as) = showParen (p > 5) $
-    shwP 6 a . showString " :| " . shwL as
-#endif
-
 #if !MIN_VERSION_binary(0, 8, 4)
 instance Binary a => Binary (NE.NonEmpty a) where
   get = fmap NE.fromList Bin.get
@@ -162,18 +152,11 @@ instance Serialise r => Serialise (NExprF r)
 instance IsString NExpr where
   fromString = Fix . NSym . fromString
 
-#if MIN_VERSION_base(4, 10, 0)
 instance Lift (Fix NExprF) where
   lift = dataToExpQ $ \b ->
     case Reflection.typeOf b `eqTypeRep` Reflection.typeRep @Text of
       Just HRefl -> Just [| pack $(liftString $ unpack b) |]
       Nothing    -> Nothing
-#else
-instance Lift (Fix NExprF) where
-    lift = dataToExpQ $ \b -> case cast b of
-        Just t -> Just [| pack $(liftString $ unpack t) |]
-        Nothing -> Nothing
-#endif
 
 -- | The monomorphic expression type is a fixed point of the polymorphic one.
 type NExpr = Fix NExprF