treewide: rm #ifdef MIN_VERSION_serialise guards

This type of #ifdef use is undocumented.

It can be explained as IF Cabal env does not load/link the package, then Cabal
does not provides this variable `MIN_VERSION_serialise`

So this expression determines is `serialise` package provided by Cabal.
b60a15d

Which was done to not load serialize for GHCJS build:
ba0dc19
(look at the `.cabal` `!impl` `GHCJS` switch)

So this macros can be reduced now.

Author: Anton-Latukha

src/Nix/Atoms.hs

@@ -3,9 +3,7 @@
 
 module Nix.Atoms where
 
-#ifdef MIN_VERSION_serialise
 import           Codec.Serialise                ( Serialise )
-#endif
 
 import           Data.Data                      ( Data)
 import           Data.Fixed                     ( mod' )
@@ -48,9 +46,7 @@ data NAtom
     , Hashable
     )
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NAtom
-#endif
 
 instance Binary NAtom
 instance ToJSON NAtom

src/Nix/Cache.hs

@@ -15,9 +15,7 @@ import           Nix.Expr.Types.Annotated
 import qualified Data.Compact                  as C
 import qualified Data.Compact.Serialize        as C
 #endif
-#ifdef MIN_VERSION_serialise
 import qualified Codec.Serialise               as S
-#endif
 
 readCache :: FilePath -> IO NExprLoc
 readCache path = do
@@ -28,25 +26,17 @@ readCache path = do
     (\ expr -> pure $ C.getCompact expr)
     eres
 #else
-#ifdef MIN_VERSION_serialise
   eres <- S.deserialiseOrFail <$> BS.readFile path
   either
     (\ err  -> fail $ "Error reading cache file: " <> show err)
     pure
     eres
-#else
-    fail "readCache not implemented for this platform"
-#endif
 #endif
 
 writeCache :: FilePath -> NExprLoc -> IO ()
 writeCache path expr =
 #ifdef USE_COMPACT
   C.writeCompact path =<< C.compact expr
 #else
-#ifdef MIN_VERSION_serialise
   BS.writeFile path (S.serialise expr)
-#else
-  fail "writeCache not implemented for this platform"
-#endif
 #endif

src/Nix/Expr/Types.hs

@@ -19,10 +19,8 @@
 -- <https://web.archive.org/web/20201112031804/https://alessandrovermeulen.me/2013/07/13/the-difference-between-shallow-and-deep-embedding/>
 module Nix.Expr.Types where
 
-#ifdef MIN_VERSION_serialise
 import qualified Codec.Serialise                as Serialise
 import           Codec.Serialise                ( Serialise )
-#endif
 import           Control.DeepSeq
 import           Data.Aeson
 import           Data.Aeson.TH
@@ -91,9 +89,7 @@ instance NFData1 Binding
 
 instance Hashable1 Binding
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (Binding r)
-#endif
 
 
 -- ** @Params@
@@ -122,9 +118,7 @@ instance Hashable1 Params
 
 instance NFData1 Params
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (Params r)
-#endif
 
 instance IsString (Params r) where
   fromString = Param . fromString
@@ -163,9 +157,7 @@ instance Hashable2 Antiquoted where
 
 instance NFData v => NFData1 (Antiquoted v)
 
-#ifdef MIN_VERSION_serialise
 instance (Serialise v, Serialise r) => Serialise (Antiquoted v r)
-#endif
 
 
 -- ** @NString@
@@ -198,9 +190,7 @@ instance Hashable1 NString
 
 instance NFData1 NString
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (NString r)
-#endif
 
 -- | For the the 'IsString' instance, we use a plain doublequoted string.
 instance IsString (NString r) where
@@ -240,7 +230,6 @@ data NKeyName r
   -- > StaticKey "x"                                     ~  x
   deriving (Eq, Ord, Generic, Typeable, Data, Show, Read, NFData, Hashable)
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (NKeyName r)
 
 instance Serialise Pos where
@@ -257,7 +246,6 @@ instance Serialise SourcePos where
       Serialise.decode
       Serialise.decode
       Serialise.decode
-#endif
 
 instance Hashable Pos where
   hashWithSalt salt = hashWithSalt salt . unPos
@@ -345,9 +333,7 @@ data NUnaryOp
   deriving (Eq, Ord, Enum, Bounded, Generic, Typeable, Data, Show, Read,
             NFData, Hashable)
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NUnaryOp
-#endif
 
 
 -- ** @NBinaryOp@
@@ -375,9 +361,7 @@ data NBinaryOp
   deriving (Eq, Ord, Enum, Bounded, Generic, Typeable, Data, Show, Read,
             NFData, Hashable)
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NBinaryOp
-#endif
 
 
 -- ** @NRecordType@
@@ -390,9 +374,7 @@ data NRecordType
   deriving (Eq, Ord, Enum, Bounded, Generic, Typeable, Data, Show, Read,
             NFData, Hashable)
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NRecordType
-#endif
 
 -- * @NExprF@ - Nix expressions, base functor
 
@@ -487,9 +469,7 @@ data NExprF r
 
 instance NFData1 NExprF
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (NExprF r)
-#endif
 
 -- | We make an `IsString` for expressions, where the string is interpreted
 -- as an identifier. This is the most common use-case...
@@ -509,9 +489,7 @@ instance Hashable1 NExprF
 -- | The monomorphic expression type is a fixed point of the polymorphic one.
 type NExpr = Fix NExprF
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NExpr
-#endif
 
 instance TH.Lift NExpr where
   lift =

src/Nix/Expr/Types/Annotated.hs

@@ -16,9 +16,7 @@ module Nix.Expr.Types.Annotated
   )
 where
 
-#ifdef MIN_VERSION_serialise
 import           Codec.Serialise
-#endif
 import           Control.DeepSeq
 import           Data.Aeson                     ( ToJSON(..)
                                                 , FromJSON(..)
@@ -63,9 +61,7 @@ instance Binary SrcSpan
 instance ToJSON SrcSpan
 instance FromJSON SrcSpan
 
-#ifdef MIN_VERSION_serialise
 instance Serialise SrcSpan
-#endif
 
 -- * data type @Ann@
 
@@ -123,31 +119,25 @@ $(deriveShow2 ''Ann)
 $(deriveJSON1 defaultOptions ''Ann)
 $(deriveJSON2 defaultOptions ''Ann)
 
-#ifdef MIN_VERSION_serialise
 instance (Serialise ann, Serialise a) => Serialise (Ann ann a)
-#endif
 
 -- ** @NExprLoc{,F}@ - annotated Nix expression
 
 type NExprLocF = AnnF SrcSpan NExprF
 
-#ifdef MIN_VERSION_serialise
 instance Serialise r => Serialise (NExprLocF r) where
   encode (AnnFP ann a) = encode ann <> encode a
   decode =
     liftA2 AnnFP
       decode
       decode
-#endif
 
 instance Binary r => Binary (NExprLocF r)
 
 -- | Annotated Nix expression (each subexpression direct to its source location).
 type NExprLoc = Fix NExprLocF
 
-#ifdef MIN_VERSION_serialise
 instance Serialise NExprLoc
-#endif
 
 instance Binary NExprLoc