{-# LANGUAGE CPP, DeriveDataTypeable, FlexibleContexts, FlexibleInstances,
GeneralizedNewtypeDeriving, IncoherentInstances, OverlappingInstances,
OverloadedStrings, UndecidableInstances, ViewPatterns #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
#ifdef GENERICS
{-# LANGUAGE DefaultSignatures #-}
#endif
module Data.Aeson.Types.Instances
(
FromJSON(..)
, ToJSON(..)
#ifdef GENERICS
, GFromJSON(..)
, GToJSON(..)
, genericToJSON
, genericParseJSON
#endif
, DotNetTime(..)
, withObject
, withText
, withArray
, withNumber
, withScientific
, withBool
, fromJSON
, (.:)
, (.:?)
, (.!=)
, (.=)
, typeMismatch
) where
import Control.Applicative ((<$>), (<*>), (<|>), pure, empty)
import Data.Aeson.Functions
import Data.Aeson.Types.Class
import Data.Aeson.Types.Internal
import Data.Scientific (Scientific)
import qualified Data.Scientific as Scientific (coefficient, base10Exponent, fromFloatDigits, toRealFloat)
import Data.Attoparsec.Number (Number(..))
import Data.Fixed
import Data.Hashable (Hashable(..))
import Data.Int (Int8, Int16, Int32, Int64)
import Data.Maybe (fromMaybe)
import Data.Monoid (Dual(..), First(..), Last(..), mappend)
import Data.Ratio (Ratio, (%), numerator, denominator)
import Data.Text (Text, pack, unpack)
import Data.Time (UTCTime, ZonedTime(..), TimeZone(..))
import Data.Time.Format (FormatTime, formatTime, parseTime)
import Data.Traversable (traverse)
import Data.Vector (Vector)
import Data.Word (Word, Word8, Word16, Word32, Word64)
import Foreign.Storable (Storable)
import System.Locale (defaultTimeLocale, dateTimeFmt)
import qualified Data.HashMap.Strict as H
import qualified Data.HashSet as HashSet
import qualified Data.IntMap as IntMap
import qualified Data.IntSet as IntSet
import qualified Data.Map as M
import qualified Data.Set as Set
import qualified Data.Tree as Tree
import qualified Data.Text as T
import qualified Data.Text.Lazy as LT
import qualified Data.Vector as V
import qualified Data.Vector.Generic as VG
import qualified Data.Vector.Primitive as VP
import qualified Data.Vector.Storable as VS
import qualified Data.Vector.Unboxed as VU
import qualified Data.Vector.Mutable as VM ( unsafeNew, unsafeWrite )
instance (ToJSON a) => ToJSON (Maybe a) where
toJSON (Just a) = toJSON a
toJSON Nothing = Null
{-# INLINE toJSON #-}
instance (FromJSON a) => FromJSON (Maybe a) where
parseJSON Null = pure Nothing
parseJSON a = Just <$> parseJSON a
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b) => ToJSON (Either a b) where
toJSON (Left a) = object [left .= a]
toJSON (Right b) = object [right .= b]
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b) => FromJSON (Either a b) where
parseJSON (Object (H.toList -> [(key, value)]))
| key == left = Left <$> parseJSON value
| key == right = Right <$> parseJSON value
parseJSON _ = fail $
"expected an object with a single property " ++
"where the property key should be either " ++
"\"Left\" or \"Right\""
{-# INLINE parseJSON #-}
left, right :: Text
left = "Left"
right = "Right"
instance ToJSON Bool where
toJSON = Bool
{-# INLINE toJSON #-}
instance FromJSON Bool where
parseJSON = withBool "Bool" pure
{-# INLINE parseJSON #-}
instance ToJSON () where
toJSON _ = emptyArray
{-# INLINE toJSON #-}
instance FromJSON () where
parseJSON = withArray "()" $ \v ->
if V.null v
then pure ()
else fail "Expected an empty array"
{-# INLINE parseJSON #-}
instance ToJSON [Char] where
toJSON = String . T.pack
{-# INLINE toJSON #-}
instance FromJSON [Char] where
parseJSON = withText "String" $ pure . T.unpack
{-# INLINE parseJSON #-}
instance ToJSON Char where
toJSON = String . T.singleton
{-# INLINE toJSON #-}
instance FromJSON Char where
parseJSON = withText "Char" $ \t ->
if T.compareLength t 1 == EQ
then pure $ T.head t
else fail "Expected a string of length 1"
{-# INLINE parseJSON #-}
instance ToJSON Scientific where
toJSON = Number
{-# INLINE toJSON #-}
instance FromJSON Scientific where
parseJSON = withScientific "Scientific" pure
{-# INLINE parseJSON #-}
instance ToJSON Double where
toJSON = realFloatToJSON
{-# INLINE toJSON #-}
instance FromJSON Double where
parseJSON = parseRealFloat "Double"
{-# INLINE parseJSON #-}
instance ToJSON Number where
toJSON (D d) = toJSON d
toJSON (I i) = toJSON i
{-# INLINE toJSON #-}
instance FromJSON Number where
parseJSON (Number s) = pure $ scientificToNumber s
parseJSON Null = pure (D (0/0))
parseJSON v = typeMismatch "Number" v
{-# INLINE parseJSON #-}
instance ToJSON Float where
toJSON = realFloatToJSON
{-# INLINE toJSON #-}
instance FromJSON Float where
parseJSON = parseRealFloat "Float"
{-# INLINE parseJSON #-}
instance ToJSON (Ratio Integer) where
toJSON r = object [ "numerator" .= numerator r
, "denominator" .= denominator r
]
{-# INLINE toJSON #-}
instance FromJSON (Ratio Integer) where
parseJSON = withObject "Rational" $ \obj ->
(%) <$> obj .: "numerator"
<*> obj .: "denominator"
{-# INLINE parseJSON #-}
instance HasResolution a => ToJSON (Fixed a) where
toJSON = Number . realToFrac
{-# INLINE toJSON #-}
instance HasResolution a => FromJSON (Fixed a) where
parseJSON = withScientific "Fixed" $ pure . realToFrac
{-# INLINE parseJSON #-}
instance ToJSON Int where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Int where
parseJSON = parseIntegral "Int"
{-# INLINE parseJSON #-}
instance ToJSON Integer where
toJSON = Number . fromInteger
{-# INLINE toJSON #-}
instance FromJSON Integer where
parseJSON = withScientific "Integral" $ pure . floor
{-# INLINE parseJSON #-}
instance ToJSON Int8 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Int8 where
parseJSON = parseIntegral "Int8"
{-# INLINE parseJSON #-}
instance ToJSON Int16 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Int16 where
parseJSON = parseIntegral "Int16"
{-# INLINE parseJSON #-}
instance ToJSON Int32 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Int32 where
parseJSON = parseIntegral "Int32"
{-# INLINE parseJSON #-}
instance ToJSON Int64 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Int64 where
parseJSON = parseIntegral "Int64"
{-# INLINE parseJSON #-}
instance ToJSON Word where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Word where
parseJSON = parseIntegral "Word"
{-# INLINE parseJSON #-}
instance ToJSON Word8 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Word8 where
parseJSON = parseIntegral "Word8"
{-# INLINE parseJSON #-}
instance ToJSON Word16 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Word16 where
parseJSON = parseIntegral "Word16"
{-# INLINE parseJSON #-}
instance ToJSON Word32 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Word32 where
parseJSON = parseIntegral "Word32"
{-# INLINE parseJSON #-}
instance ToJSON Word64 where
toJSON = Number . fromIntegral
{-# INLINE toJSON #-}
instance FromJSON Word64 where
parseJSON = parseIntegral "Word64"
{-# INLINE parseJSON #-}
instance ToJSON Text where
toJSON = String
{-# INLINE toJSON #-}
instance FromJSON Text where
parseJSON = withText "Text" pure
{-# INLINE parseJSON #-}
instance ToJSON LT.Text where
toJSON = String . LT.toStrict
{-# INLINE toJSON #-}
instance FromJSON LT.Text where
parseJSON = withText "Lazy Text" $ pure . LT.fromStrict
{-# INLINE parseJSON #-}
instance (ToJSON a) => ToJSON [a] where
toJSON = Array . V.fromList . map toJSON
{-# INLINE toJSON #-}
instance (FromJSON a) => FromJSON [a] where
parseJSON = withArray "[a]" $ mapM parseJSON . V.toList
{-# INLINE parseJSON #-}
instance (ToJSON a) => ToJSON (Vector a) where
toJSON = Array . V.map toJSON
{-# INLINE toJSON #-}
instance (FromJSON a) => FromJSON (Vector a) where
parseJSON = withArray "Vector a" $ V.mapM parseJSON
{-# INLINE parseJSON #-}
vectorToJSON :: (VG.Vector v a, ToJSON a) => v a -> Value
vectorToJSON = Array . V.map toJSON . V.convert
{-# INLINE vectorToJSON #-}
vectorParseJSON :: (FromJSON a, VG.Vector w a) => String -> Value -> Parser (w a)
vectorParseJSON s = withArray s $ fmap V.convert . V.mapM parseJSON
{-# INLINE vectorParseJSON #-}
instance (Storable a, ToJSON a) => ToJSON (VS.Vector a) where
toJSON = vectorToJSON
instance (Storable a, FromJSON a) => FromJSON (VS.Vector a) where
parseJSON = vectorParseJSON "Data.Vector.Storable.Vector a"
instance (VP.Prim a, ToJSON a) => ToJSON (VP.Vector a) where
toJSON = vectorToJSON
instance (VP.Prim a, FromJSON a) => FromJSON (VP.Vector a) where
parseJSON = vectorParseJSON "Data.Vector.Primitive.Vector a"
instance (VG.Vector VU.Vector a, ToJSON a) => ToJSON (VU.Vector a) where
toJSON = vectorToJSON
instance (VG.Vector VU.Vector a, FromJSON a) => FromJSON (VU.Vector a) where
parseJSON = vectorParseJSON "Data.Vector.Unboxed.Vector a"
instance (ToJSON a) => ToJSON (Set.Set a) where
toJSON = toJSON . Set.toList
{-# INLINE toJSON #-}
instance (Ord a, FromJSON a) => FromJSON (Set.Set a) where
parseJSON = fmap Set.fromList . parseJSON
{-# INLINE parseJSON #-}
instance (ToJSON a) => ToJSON (HashSet.HashSet a) where
toJSON = toJSON . HashSet.toList
{-# INLINE toJSON #-}
instance (Eq a, Hashable a, FromJSON a) => FromJSON (HashSet.HashSet a) where
parseJSON = fmap HashSet.fromList . parseJSON
{-# INLINE parseJSON #-}
instance ToJSON IntSet.IntSet where
toJSON = toJSON . IntSet.toList
{-# INLINE toJSON #-}
instance FromJSON IntSet.IntSet where
parseJSON = fmap IntSet.fromList . parseJSON
{-# INLINE parseJSON #-}
instance ToJSON a => ToJSON (IntMap.IntMap a) where
toJSON = toJSON . IntMap.toList
{-# INLINE toJSON #-}
instance FromJSON a => FromJSON (IntMap.IntMap a) where
parseJSON = fmap IntMap.fromList . parseJSON
{-# INLINE parseJSON #-}
instance (ToJSON v) => ToJSON (M.Map Text v) where
toJSON = Object . M.foldrWithKey (\k -> H.insert k . toJSON) H.empty
{-# INLINE toJSON #-}
instance (FromJSON v) => FromJSON (M.Map Text v) where
parseJSON = withObject "Map Text a" $
fmap (H.foldrWithKey M.insert M.empty) . traverse parseJSON
instance (ToJSON v) => ToJSON (M.Map LT.Text v) where
toJSON = Object . mapHashKeyVal LT.toStrict toJSON
instance (FromJSON v) => FromJSON (M.Map LT.Text v) where
parseJSON = fmap (hashMapKey LT.fromStrict) . parseJSON
instance (ToJSON v) => ToJSON (M.Map String v) where
toJSON = Object . mapHashKeyVal pack toJSON
instance (FromJSON v) => FromJSON (M.Map String v) where
parseJSON = fmap (hashMapKey unpack) . parseJSON
instance (ToJSON v) => ToJSON (H.HashMap Text v) where
toJSON = Object . H.map toJSON
{-# INLINE toJSON #-}
instance (FromJSON v) => FromJSON (H.HashMap Text v) where
parseJSON = withObject "HashMap Text a" $ traverse parseJSON
instance (ToJSON v) => ToJSON (H.HashMap LT.Text v) where
toJSON = Object . mapKeyVal LT.toStrict toJSON
instance (FromJSON v) => FromJSON (H.HashMap LT.Text v) where
parseJSON = fmap (mapKey LT.fromStrict) . parseJSON
instance (ToJSON v) => ToJSON (H.HashMap String v) where
toJSON = Object . mapKeyVal pack toJSON
instance (FromJSON v) => FromJSON (H.HashMap String v) where
parseJSON = fmap (mapKey unpack) . parseJSON
instance (ToJSON v) => ToJSON (Tree.Tree v) where
toJSON (Tree.Node root branches) = toJSON (root,branches)
instance (FromJSON v) => FromJSON (Tree.Tree v) where
parseJSON j = uncurry Tree.Node <$> parseJSON j
instance ToJSON Value where
toJSON a = a
{-# INLINE toJSON #-}
instance FromJSON Value where
parseJSON a = pure a
{-# INLINE parseJSON #-}
instance ToJSON DotNetTime where
toJSON (DotNetTime t) =
String (pack (secs ++ formatMillis t ++ ")/"))
where secs = formatTime defaultTimeLocale "/Date(%s" t
{-# INLINE toJSON #-}
instance FromJSON DotNetTime where
parseJSON = withText "DotNetTime" $ \t ->
let (s,m) = T.splitAt (T.length t - 5) t
t' = T.concat [s,".",m]
in case parseTime defaultTimeLocale "/Date(%s%Q)/" (unpack t') of
Just d -> pure (DotNetTime d)
_ -> fail "could not parse .NET time"
{-# INLINE parseJSON #-}
instance ToJSON ZonedTime where
toJSON t = String $ pack $ formatTime defaultTimeLocale format t
where
format = "%FT%T." ++ formatMillis t ++ tzFormat
tzFormat
| 0 == timeZoneMinutes (zonedTimeZone t) = "Z"
| otherwise = "%z"
formatMillis :: (FormatTime t) => t -> String
formatMillis t = take 3 . formatTime defaultTimeLocale "%q" $ t
instance FromJSON ZonedTime where
parseJSON (String t) =
tryFormats alternateFormats
<|> fail "could not parse ECMA-262 ISO-8601 date"
where
tryFormat f =
case parseTime defaultTimeLocale f (unpack t) of
Just d -> pure d
Nothing -> empty
tryFormats = foldr1 (<|>) . map tryFormat
alternateFormats =
dateTimeFmt defaultTimeLocale :
distributeList ["%Y", "%Y-%m", "%F"]
["T%R", "T%T", "T%T%Q", "T%T%QZ", "T%T%Q%z"]
distributeList xs ys =
foldr (\x acc -> acc ++ distribute x ys) [] xs
distribute x = map (mappend x)
parseJSON v = typeMismatch "ZonedTime" v
instance ToJSON UTCTime where
toJSON t = String (pack (take 23 str ++ "Z"))
where str = formatTime defaultTimeLocale "%FT%T.%q" t
{-# INLINE toJSON #-}
instance FromJSON UTCTime where
parseJSON = withText "UTCTime" $ \t ->
case parseTime defaultTimeLocale "%FT%T%QZ" (unpack t) of
Just d -> pure d
_ -> fail "could not parse ISO-8601 date"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b) => ToJSON (a,b) where
toJSON (a,b) = Array $ V.create $ do
mv <- VM.unsafeNew 2
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b) => FromJSON (a,b) where
parseJSON = withArray "(a,b)" $ \ab ->
let n = V.length ab
in if n == 2
then (,) <$> parseJSON (V.unsafeIndex ab 0)
<*> parseJSON (V.unsafeIndex ab 1)
else fail $ "cannot unpack array of length " ++
show n ++ " into a pair"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b, ToJSON c) => ToJSON (a,b,c) where
toJSON (a,b,c) = Array $ V.create $ do
mv <- VM.unsafeNew 3
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
VM.unsafeWrite mv 2 (toJSON c)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b, FromJSON c) => FromJSON (a,b,c) where
parseJSON = withArray "(a,b,c)" $ \abc ->
let n = V.length abc
in if n == 3
then (,,) <$> parseJSON (V.unsafeIndex abc 0)
<*> parseJSON (V.unsafeIndex abc 1)
<*> parseJSON (V.unsafeIndex abc 2)
else fail $ "cannot unpack array of length " ++
show n ++ " into a 3-tuple"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON (a,b,c,d) where
toJSON (a,b,c,d) = Array $ V.create $ do
mv <- VM.unsafeNew 4
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
VM.unsafeWrite mv 2 (toJSON c)
VM.unsafeWrite mv 3 (toJSON d)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON (a,b,c,d) where
parseJSON = withArray "(a,b,c,d)" $ \abcd ->
let n = V.length abcd
in if n == 4
then (,,,) <$> parseJSON (V.unsafeIndex abcd 0)
<*> parseJSON (V.unsafeIndex abcd 1)
<*> parseJSON (V.unsafeIndex abcd 2)
<*> parseJSON (V.unsafeIndex abcd 3)
else fail $ "cannot unpack array of length " ++
show n ++ " into a 4-tuple"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON (a,b,c,d,e) where
toJSON (a,b,c,d,e) = Array $ V.create $ do
mv <- VM.unsafeNew 5
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
VM.unsafeWrite mv 2 (toJSON c)
VM.unsafeWrite mv 3 (toJSON d)
VM.unsafeWrite mv 4 (toJSON e)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON (a,b,c,d,e) where
parseJSON = withArray "(a,b,c,d,e)" $ \abcde ->
let n = V.length abcde
in if n == 5
then (,,,,) <$> parseJSON (V.unsafeIndex abcde 0)
<*> parseJSON (V.unsafeIndex abcde 1)
<*> parseJSON (V.unsafeIndex abcde 2)
<*> parseJSON (V.unsafeIndex abcde 3)
<*> parseJSON (V.unsafeIndex abcde 4)
else fail $ "cannot unpack array of length " ++
show n ++ " into a 5-tuple"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON (a,b,c,d,e,f) where
toJSON (a,b,c,d,e,f) = Array $ V.create $ do
mv <- VM.unsafeNew 6
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
VM.unsafeWrite mv 2 (toJSON c)
VM.unsafeWrite mv 3 (toJSON d)
VM.unsafeWrite mv 4 (toJSON e)
VM.unsafeWrite mv 5 (toJSON f)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON (a,b,c,d,e,f) where
parseJSON = withArray "(a,b,c,d,e,f)" $ \abcdef ->
let n = V.length abcdef
in if n == 6
then (,,,,,) <$> parseJSON (V.unsafeIndex abcdef 0)
<*> parseJSON (V.unsafeIndex abcdef 1)
<*> parseJSON (V.unsafeIndex abcdef 2)
<*> parseJSON (V.unsafeIndex abcdef 3)
<*> parseJSON (V.unsafeIndex abcdef 4)
<*> parseJSON (V.unsafeIndex abcdef 5)
else fail $ "cannot unpack array of length " ++
show n ++ " into a 6-tuple"
{-# INLINE parseJSON #-}
instance (ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON (a,b,c,d,e,f,g) where
toJSON (a,b,c,d,e,f,g) = Array $ V.create $ do
mv <- VM.unsafeNew 7
VM.unsafeWrite mv 0 (toJSON a)
VM.unsafeWrite mv 1 (toJSON b)
VM.unsafeWrite mv 2 (toJSON c)
VM.unsafeWrite mv 3 (toJSON d)
VM.unsafeWrite mv 4 (toJSON e)
VM.unsafeWrite mv 5 (toJSON f)
VM.unsafeWrite mv 6 (toJSON g)
return mv
{-# INLINE toJSON #-}
instance (FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON (a,b,c,d,e,f,g) where
parseJSON = withArray "(a,b,c,d,e,f,g)" $ \abcdefg ->
let n = V.length abcdefg
in if n == 7
then (,,,,,,) <$> parseJSON (V.unsafeIndex abcdefg 0)
<*> parseJSON (V.unsafeIndex abcdefg 1)
<*> parseJSON (V.unsafeIndex abcdefg 2)
<*> parseJSON (V.unsafeIndex abcdefg 3)
<*> parseJSON (V.unsafeIndex abcdefg 4)
<*> parseJSON (V.unsafeIndex abcdefg 5)
<*> parseJSON (V.unsafeIndex abcdefg 6)
else fail $ "cannot unpack array of length " ++
show n ++ " into a 7-tuple"
{-# INLINE parseJSON #-}
instance ToJSON a => ToJSON (Dual a) where
toJSON = toJSON . getDual
{-# INLINE toJSON #-}
instance FromJSON a => FromJSON (Dual a) where
parseJSON = fmap Dual . parseJSON
{-# INLINE parseJSON #-}
instance ToJSON a => ToJSON (First a) where
toJSON = toJSON . getFirst
{-# INLINE toJSON #-}
instance FromJSON a => FromJSON (First a) where
parseJSON = fmap First . parseJSON
{-# INLINE parseJSON #-}
instance ToJSON a => ToJSON (Last a) where
toJSON = toJSON . getLast
{-# INLINE toJSON #-}
instance FromJSON a => FromJSON (Last a) where
parseJSON = fmap Last . parseJSON
{-# INLINE parseJSON #-}
withObject :: String -> (Object -> Parser a) -> Value -> Parser a
withObject _ f (Object obj) = f obj
withObject expected _ v = typeMismatch expected v
{-# INLINE withObject #-}
withText :: String -> (Text -> Parser a) -> Value -> Parser a
withText _ f (String txt) = f txt
withText expected _ v = typeMismatch expected v
{-# INLINE withText #-}
withArray :: String -> (Array -> Parser a) -> Value -> Parser a
withArray _ f (Array arr) = f arr
withArray expected _ v = typeMismatch expected v
{-# INLINE withArray #-}
withNumber :: String -> (Number -> Parser a) -> Value -> Parser a
withNumber expected f = withScientific expected (f . scientificToNumber)
{-# INLINE withNumber #-}
{-# DEPRECATED withNumber "Use withScientific instead" #-}
withScientific :: String -> (Scientific -> Parser a) -> Value -> Parser a
withScientific _ f (Number scientific) = f scientific
withScientific expected _ v = typeMismatch expected v
{-# INLINE withScientific #-}
withBool :: String -> (Bool -> Parser a) -> Value -> Parser a
withBool _ f (Bool arr) = f arr
withBool expected _ v = typeMismatch expected v
{-# INLINE withBool #-}
(.=) :: ToJSON a => Text -> a -> Pair
name .= value = (name, toJSON value)
{-# INLINE (.=) #-}
fromJSON :: (FromJSON a) => Value -> Result a
fromJSON = parse parseJSON
{-# INLINE fromJSON #-}
(.:) :: (FromJSON a) => Object -> Text -> Parser a
obj .: key = case H.lookup key obj of
Nothing -> fail $ "key " ++ show key ++ " not present"
Just v -> parseJSON v
{-# INLINE (.:) #-}
(.:?) :: (FromJSON a) => Object -> Text -> Parser (Maybe a)
obj .:? key = case H.lookup key obj of
Nothing -> pure Nothing
Just v -> parseJSON v
{-# INLINE (.:?) #-}
(.!=) :: Parser (Maybe a) -> a -> Parser a
pmval .!= val = fromMaybe val <$> pmval
{-# INLINE (.!=) #-}
typeMismatch :: String
-> Value
-> Parser a
typeMismatch expected actual =
fail $ "when expecting a " ++ expected ++ ", encountered " ++ name ++
" instead"
where
name = case actual of
Object _ -> "Object"
Array _ -> "Array"
String _ -> "String"
Number _ -> "Number"
Bool _ -> "Boolean"
Null -> "Null"
realFloatToJSON :: RealFloat a => a -> Value
realFloatToJSON d
| isNaN d || isInfinite d = Null
| otherwise = Number $ Scientific.fromFloatDigits d
{-# INLINE realFloatToJSON #-}
scientificToNumber :: Scientific -> Number
scientificToNumber s
| e < 0 = D $ Scientific.toRealFloat s
| otherwise = I $ c * 10 ^ e
where
e = Scientific.base10Exponent s
c = Scientific.coefficient s
{-# INLINE scientificToNumber #-}
parseRealFloat :: RealFloat a => String -> Value -> Parser a
parseRealFloat _ (Number s) = pure $ Scientific.toRealFloat s
parseRealFloat _ Null = pure (0/0)
parseRealFloat expected v = typeMismatch expected v
{-# INLINE parseRealFloat #-}
parseIntegral :: Integral a => String -> Value -> Parser a
parseIntegral expected = withScientific expected $ pure . floor
{-# INLINE parseIntegral #-}