551f191 · typeable/aeson

git.iko.soy/typeable/aeson

Instances for Void/V1

commit551f191178f32ce41c0293d14fffa672579d22a2 authorWill Yager <will.yager@gmail.com> dateSat 18 Aug 2018, 19:51 (8 years ago) parent1a322a1

2 files changed+24−1

compare with master

unifiedsplit

Data/Aeson/Types/FromJSON.hs+9−1 Data/Aeson/Types/ToJSON.hs+15

Data/Aeson/Types/FromJSON.hs+9−1

@@ -107,6 +107,7 @@ import Data.Time.Locale.Compat (defaultTimeLocale)

107107import Data.Traversable as Tr (sequence)

108108import Data.Vector (Vector)

109109import Data.Version (Version, parseVersion)

110+import Data.Void (Void)

110111import Data.Word (Word16, Word32, Word64, Word8)

111112import Foreign.Storable (Storable)

112113import Foreign.C.Types (CTime (..))

@@ -786,6 +787,11 @@ pmval .!= val = fromMaybe val <$> pmval

786787-- Generic parseJSON

787788-------------------------------------------------------------------------------

788789

790+instance GFromJSON arity V1 where

791+ -- Whereof we cannot format, thereof we cannot parse:

792+ gParseJSON _ _ _ = fail "Attempted to parse empty type"

793+

794+

789795instance OVERLAPPABLE_ (GFromJSON arity a) => GFromJSON arity (M1 i c a) where

790796 -- Meta-information, which is not handled elsewhere, is just added to the

791797 -- parsed value:

@@ -1198,7 +1204,9 @@ instance (FromJSON a, FromJSON b) => FromJSON (Either a b) where

11981204 parseJSON = parseJSON2

11991205 {-# INLINE parseJSON #-}

12001206

1201−

1207+instance FromJSON Void where

1208+ parseJSON _ = fail "Cannot parse Void"

1209+ {-# INLINE parseJSON #-}

12021210

12031211instance FromJSON Bool where

12041212 parseJSON = withBool "Bool" pure

Data/Aeson/Types/ToJSON.hs+15

@@ -14,6 +14,7 @@

1414{-# LANGUAGE TypeOperators #-}

1515{-# LANGUAGE TypeSynonymInstances #-}

1616{-# LANGUAGE UndecidableInstances #-}

17+{-# LANGUAGE EmptyCase #-}

1718

1819#if __GLASGOW_HASKELL__ >= 706

1920{-# LANGUAGE PolyKinds #-}

@@ -91,6 +92,7 @@ import Data.Time.Format (FormatTime, formatTime)

9192import Data.Time.Locale.Compat (defaultTimeLocale)

9293import Data.Vector (Vector)

9394import Data.Version (Version, showVersion)

95+import Data.Void (Void)

9496import Data.Word (Word16, Word32, Word64, Word8)

9597import Foreign.Storable (Storable)

9698import Foreign.C.Types (CTime (..))

@@ -702,6 +704,12 @@ instance ( AllNullary (a :+: b) allNullary

702704-- possible but makes error messages a bit harder to understand for missing

703705-- instances.

704706

707+instance GToJSON Value arity V1 where

708+ -- Empty values do not exist, which makes the job of formatting them

709+ -- rather easy:

710+ gToJSON _ _ x = case x of {}

711+ {-# INLINE gToJSON #-}

712+

705713instance ToJSON a => GToJSON Value arity (K1 i a) where

706714 -- Constant values are encoded using their ToJSON instance:

707715 gToJSON _opts _ = toJSON . unK1

@@ -1221,6 +1229,13 @@ instance (ToJSON a, ToJSON b) => ToJSON (Either a b) where

12211229 toEncoding = toEncoding2

12221230 {-# INLINE toEncoding #-}

12231231

1232+instance ToJSON Void where

1233+ toJSON x = case x of {}

1234+ {-# INLINE toJSON #-}

1235+

1236+ toEncoding x = case x of {}

1237+ {-# INLINE toEncoding #-}

1238+

12241239

12251240instance ToJSON Bool where

12261241 toJSON = Bool