Safe Haskell	None
Language	Haskell2010

Generics.SOP.JSON

Contents

Configuration
JSON view of a datatype
Generic functions
UpdateFromJSON and co
Re-exports

Synopsis

Configuration

type JsonFieldName = String Source #

type JsonTagName = String Source #

data JsonOptions Source #

JSON encoder/decoder configuration

Constructors

JsonOptions
Fields jsonFieldName :: DatatypeName -> FieldName -> JsonFieldName Construct the name for JSON object fields (not for the tags that are used for sum-types, however) The default just uses the name of the corresponding Haskell constructor jsonTagName :: ConstructorName -> JsonTagName Construct the name for a tag for sum-types. The default just uses the name of the Haskell constructor.

defaultJsonOptions :: JsonOptions Source #

JSON view of a datatype

data Tag Source #

Constructor tag

For a datatype with a single constructor we do not need to tag values with their constructor; but for a datatype with multiple constructors we do.

Constructors

NoTag
Tag JsonTagName

data JsonInfo :: [*] -> * where Source #

Constructors

JsonZero :: ConstructorName -> JsonInfo '[]
JsonOne :: Tag -> JsonInfo '[a]
JsonMultiple :: SListI xs => Tag -> JsonInfo xs
JsonRecord :: SListI xs => Tag -> NP (K String) xs -> JsonInfo xs

jsonInfo :: forall a. (HasDatatypeInfo a, SListI (Code a)) => Proxy a -> JsonOptions -> NP JsonInfo (Code a) Source #

Generic functions

gtoJSON :: forall a. (Generic a, HasDatatypeInfo a, All2 ToJSON (Code a)) => JsonOptions -> a -> Value Source #

gparseJSON :: forall a. (Generic a, HasDatatypeInfo a, All2 FromJSON (Code a)) => JsonOptions -> Value -> Parser a Source #

UpdateFromJSON and co

class UpdateFromJSON a where Source #

For some values we can support "updating" the value with a "partial" JSON value; record types are the prime example (and the only one supported by the generic function). For non-record types we typically can only replace the value with a "complete" JSON value; in this case, we simply ignore the old value (see replaceWithJSON). Typical class instances will look like

instance UpdateFromJSON SomeRecordType where
   updateFromJSON = gupdateFromJSON <jsonOptions>

or

instance UpdateFromJSON SomeNonRecordType where
   updateFromJSON = replaceWithJSON

NOTE: The generic function uses one-level lenses for the object fields. We could generalize this to arbitrary paths, but then the type would change to

updateFromJSON :: Value -> Parser (a -> UpdateM a)

I.e., updating a value from JSON would, in general, involve a database write.

Minimal complete definition

updateFromJSON

Methods

updateFromJSON :: Value -> Parser (a -> a) Source #

Instances

UpdateFromJSON Bool Source #
Methods updateFromJSON :: Value -> Parser (Bool -> Bool) Source #
UpdateFromJSON Double Source #
Methods updateFromJSON :: Value -> Parser (Double -> Double) Source #
UpdateFromJSON Int Source #
Methods updateFromJSON :: Value -> Parser (Int -> Int) Source #
UpdateFromJSON Rational Source #
Methods updateFromJSON :: Value -> Parser (Rational -> Rational) Source #
UpdateFromJSON String Source #
Methods updateFromJSON :: Value -> Parser (String -> String) Source #
UpdateFromJSON Text Source #
Methods updateFromJSON :: Value -> Parser (Text -> Text) Source #
FromJSON a => UpdateFromJSON [a] Source #
Methods updateFromJSON :: Value -> Parser ([a] -> [a]) Source #
FromJSON a => UpdateFromJSON (Maybe a) Source #
Methods updateFromJSON :: Value -> Parser (Maybe a -> Maybe a) Source #

gupdateFromJSON :: forall a xs. (Generic a, HasDatatypeInfo a, All UpdateFromJSON xs, Code a ~ '[xs]) => JsonOptions -> Value -> Parser (a -> a) Source #

Construct a function that updates a value of some record type, given a JSON object with new values for some (or none, or all) of the fields

replaceWithJSON :: FromJSON a => Value -> Parser (a -> a) Source #

For types that we can only replace "whole", rather than update field by field

parseWith :: UpdateFromJSON a => a -> Value -> Parser a Source #

Conversely, for types that we can only parse if we have a starting point

Re-exports

class ToJSON a where #

A type that can be converted to JSON.

Instances in general must specify toJSON and should (but don't need to) specify toEncoding.

An example type and instance:

-- Allow ourselves to write Text literals.
{-# LANGUAGE OverloadedStrings #-}

data Coord = Coord { x :: Double, y :: Double }

instance ToJSON Coord where
  toJSON (Coord x y) = object ["x" .= x, "y" .= y]

  toEncoding (Coord x y) = pairs ("x" .= x <> "y" .= y)

Instead of manually writing your ToJSON instance, there are two options to do it automatically:

Data.Aeson.TH provides Template Haskell functions which will derive an instance at compile time. The generated instance is optimized for your type so it will probably be more efficient than the following option.
The compiler can provide a default generic implementation for toJSON.

To use the second, simply add a deriving Generic clause to your datatype and declare a ToJSON instance. If you require nothing other than defaultOptions, it is sufficient to write (and this is the only alternative where the default toJSON implementation is sufficient):

{-# LANGUAGE DeriveGeneric #-}

import GHC.Generics

data Coord = Coord { x :: Double, y :: Double } deriving Generic

instance ToJSON Coord where
    toEncoding = genericToEncoding defaultOptions

If on the other hand you wish to customize the generic decoding, you have to implement both methods:

customOptions = defaultOptions
                { fieldLabelModifier = map toUpper
                }

instance ToJSON Coord where
    toJSON     = genericToJSON customOptions
    toEncoding = genericToEncoding customOptions

Previous versions of this library only had the toJSON method. Adding toEncoding had to reasons:

toEncoding is more efficient for the common case that the output of toJSON is directly serialized to a ByteString. Further, expressing either method in terms of the other would be non-optimal.
The choice of defaults allows a smooth transition for existing users: Existing instances that do not define toEncoding still compile and have the correct semantics. This is ensured by making the default implementation of toEncoding use toJSON. This produces correct results, but since it performs an intermediate conversion to a Value, it will be less efficient than directly emitting an Encoding. (this also means that specifying nothing more than instance ToJSON Coord would be sufficient as a generically decoding instance, but there probably exists no good reason to not specify toEncoding in new instances.)

Methods

toJSON :: a -> Value #

Convert a Haskell value to a JSON-friendly intermediate type.

toEncoding :: a -> Encoding #

Encode a Haskell value as JSON.

The default implementation of this method creates an intermediate Value using toJSON. This provides source-level compatibility for people upgrading from older versions of this library, but obviously offers no performance advantage.

To benefit from direct encoding, you must provide an implementation for this method. The easiest way to do so is by having your types implement Generic using the DeriveGeneric extension, and then have GHC generate a method body as follows.

instance ToJSON Coord where
    toEncoding = genericToEncoding defaultOptions

toJSONList :: [a] -> Value #

toEncodingList :: [a] -> Encoding #

Instances

ToJSON Bool
Methods toJSON :: Bool -> Value # toEncoding :: Bool -> Encoding # toJSONList :: [Bool] -> Value # toEncodingList :: [Bool] -> Encoding #
ToJSON Char
Methods toJSON :: Char -> Value # toEncoding :: Char -> Encoding # toJSONList :: [Char] -> Value # toEncodingList :: [Char] -> Encoding #
ToJSON Double
Methods toJSON :: Double -> Value # toEncoding :: Double -> Encoding # toJSONList :: [Double] -> Value # toEncodingList :: [Double] -> Encoding #
ToJSON Float
Methods toJSON :: Float -> Value # toEncoding :: Float -> Encoding # toJSONList :: [Float] -> Value # toEncodingList :: [Float] -> Encoding #
ToJSON Int
Methods toJSON :: Int -> Value # toEncoding :: Int -> Encoding # toJSONList :: [Int] -> Value # toEncodingList :: [Int] -> Encoding #
ToJSON Int8
Methods toJSON :: Int8 -> Value # toEncoding :: Int8 -> Encoding # toJSONList :: [Int8] -> Value # toEncodingList :: [Int8] -> Encoding #
ToJSON Int16
Methods toJSON :: Int16 -> Value # toEncoding :: Int16 -> Encoding # toJSONList :: [Int16] -> Value # toEncodingList :: [Int16] -> Encoding #
ToJSON Int32
Methods toJSON :: Int32 -> Value # toEncoding :: Int32 -> Encoding # toJSONList :: [Int32] -> Value # toEncodingList :: [Int32] -> Encoding #
ToJSON Int64
Methods toJSON :: Int64 -> Value # toEncoding :: Int64 -> Encoding # toJSONList :: [Int64] -> Value # toEncodingList :: [Int64] -> Encoding #
ToJSON Integer
Methods toJSON :: Integer -> Value # toEncoding :: Integer -> Encoding # toJSONList :: [Integer] -> Value # toEncodingList :: [Integer] -> Encoding #
ToJSON Ordering
Methods toJSON :: Ordering -> Value # toEncoding :: Ordering -> Encoding # toJSONList :: [Ordering] -> Value # toEncodingList :: [Ordering] -> Encoding #
ToJSON Word
Methods toJSON :: Word -> Value # toEncoding :: Word -> Encoding # toJSONList :: [Word] -> Value # toEncodingList :: [Word] -> Encoding #
ToJSON Word8
Methods toJSON :: Word8 -> Value # toEncoding :: Word8 -> Encoding # toJSONList :: [Word8] -> Value # toEncodingList :: [Word8] -> Encoding #
ToJSON Word16
Methods toJSON :: Word16 -> Value # toEncoding :: Word16 -> Encoding # toJSONList :: [Word16] -> Value # toEncodingList :: [Word16] -> Encoding #
ToJSON Word32
Methods toJSON :: Word32 -> Value # toEncoding :: Word32 -> Encoding # toJSONList :: [Word32] -> Value # toEncodingList :: [Word32] -> Encoding #
ToJSON Word64
Methods toJSON :: Word64 -> Value # toEncoding :: Word64 -> Encoding # toJSONList :: [Word64] -> Value # toEncodingList :: [Word64] -> Encoding #
ToJSON ()
Methods toJSON :: () -> Value # toEncoding :: () -> Encoding # toJSONList :: [()] -> Value # toEncodingList :: [()] -> Encoding #
ToJSON Scientific
Methods toJSON :: Scientific -> Value # toEncoding :: Scientific -> Encoding # toJSONList :: [Scientific] -> Value # toEncodingList :: [Scientific] -> Encoding #
ToJSON Number
Methods toJSON :: Number -> Value # toEncoding :: Number -> Encoding # toJSONList :: [Number] -> Value # toEncodingList :: [Number] -> Encoding #
ToJSON Text
Methods toJSON :: Text -> Value # toEncoding :: Text -> Encoding # toJSONList :: [Text] -> Value # toEncodingList :: [Text] -> Encoding #
ToJSON UTCTime
Methods toJSON :: UTCTime -> Value # toEncoding :: UTCTime -> Encoding # toJSONList :: [UTCTime] -> Value # toEncodingList :: [UTCTime] -> Encoding #
ToJSON Value
Methods toJSON :: Value -> Value # toEncoding :: Value -> Encoding # toJSONList :: [Value] -> Value # toEncodingList :: [Value] -> Encoding #
ToJSON DotNetTime
Methods toJSON :: DotNetTime -> Value # toEncoding :: DotNetTime -> Encoding # toJSONList :: [DotNetTime] -> Value # toEncodingList :: [DotNetTime] -> Encoding #
ToJSON Text
Methods toJSON :: Text -> Value # toEncoding :: Text -> Encoding # toJSONList :: [Text] -> Value # toEncodingList :: [Text] -> Encoding #
ToJSON Natural
Methods toJSON :: Natural -> Value # toEncoding :: Natural -> Encoding # toJSONList :: [Natural] -> Value # toEncodingList :: [Natural] -> Encoding #
ToJSON Version
Methods toJSON :: Version -> Value # toEncoding :: Version -> Encoding # toJSONList :: [Version] -> Value # toEncodingList :: [Version] -> Encoding #
ToJSON IntSet
Methods toJSON :: IntSet -> Value # toEncoding :: IntSet -> Encoding # toJSONList :: [IntSet] -> Value # toEncodingList :: [IntSet] -> Encoding #
ToJSON LocalTime
Methods toJSON :: LocalTime -> Value # toEncoding :: LocalTime -> Encoding # toJSONList :: [LocalTime] -> Value # toEncodingList :: [LocalTime] -> Encoding #
ToJSON ZonedTime
Methods toJSON :: ZonedTime -> Value # toEncoding :: ZonedTime -> Encoding # toJSONList :: [ZonedTime] -> Value # toEncodingList :: [ZonedTime] -> Encoding #
ToJSON TimeOfDay
Methods toJSON :: TimeOfDay -> Value # toEncoding :: TimeOfDay -> Encoding # toJSONList :: [TimeOfDay] -> Value # toEncodingList :: [TimeOfDay] -> Encoding #
ToJSON NominalDiffTime
Methods toJSON :: NominalDiffTime -> Value # toEncoding :: NominalDiffTime -> Encoding # toJSONList :: [NominalDiffTime] -> Value # toEncodingList :: [NominalDiffTime] -> Encoding #
ToJSON Day
Methods toJSON :: Day -> Value # toEncoding :: Day -> Encoding # toJSONList :: [Day] -> Value # toEncodingList :: [Day] -> Encoding #
ToJSON UUID
Methods toJSON :: UUID -> Value # toEncoding :: UUID -> Encoding # toJSONList :: [UUID] -> Value # toEncodingList :: [UUID] -> Encoding #
ToJSON a => ToJSON [a]
Methods toJSON :: [a] -> Value # toEncoding :: [a] -> Encoding # toJSONList :: [[a]] -> Value # toEncodingList :: [[a]] -> Encoding #
ToJSON a => ToJSON (Maybe a)
Methods toJSON :: Maybe a -> Value # toEncoding :: Maybe a -> Encoding # toJSONList :: [Maybe a] -> Value # toEncodingList :: [Maybe a] -> Encoding #
(ToJSON a, Integral a) => ToJSON (Ratio a)
Methods toJSON :: Ratio a -> Value # toEncoding :: Ratio a -> Encoding # toJSONList :: [Ratio a] -> Value # toEncodingList :: [Ratio a] -> Encoding #
ToJSON a => ToJSON (Identity a)
Methods toJSON :: Identity a -> Value # toEncoding :: Identity a -> Encoding # toJSONList :: [Identity a] -> Value # toEncodingList :: [Identity a] -> Encoding #
ToJSON a => ToJSON (Min a)
Methods toJSON :: Min a -> Value # toEncoding :: Min a -> Encoding # toJSONList :: [Min a] -> Value # toEncodingList :: [Min a] -> Encoding #
ToJSON a => ToJSON (Max a)
Methods toJSON :: Max a -> Value # toEncoding :: Max a -> Encoding # toJSONList :: [Max a] -> Value # toEncodingList :: [Max a] -> Encoding #
ToJSON a => ToJSON (First a)
Methods toJSON :: First a -> Value # toEncoding :: First a -> Encoding # toJSONList :: [First a] -> Value # toEncodingList :: [First a] -> Encoding #
ToJSON a => ToJSON (Last a)
Methods toJSON :: Last a -> Value # toEncoding :: Last a -> Encoding # toJSONList :: [Last a] -> Value # toEncodingList :: [Last a] -> Encoding #
ToJSON a => ToJSON (WrappedMonoid a)
Methods toJSON :: WrappedMonoid a -> Value # toEncoding :: WrappedMonoid a -> Encoding # toJSONList :: [WrappedMonoid a] -> Value # toEncodingList :: [WrappedMonoid a] -> Encoding #
ToJSON a => ToJSON (Option a)
Methods toJSON :: Option a -> Value # toEncoding :: Option a -> Encoding # toJSONList :: [Option a] -> Value # toEncodingList :: [Option a] -> Encoding #
ToJSON a => ToJSON (NonEmpty a)
Methods toJSON :: NonEmpty a -> Value # toEncoding :: NonEmpty a -> Encoding # toJSONList :: [NonEmpty a] -> Value # toEncodingList :: [NonEmpty a] -> Encoding #
HasResolution a => ToJSON (Fixed a)
Methods toJSON :: Fixed a -> Value # toEncoding :: Fixed a -> Encoding # toJSONList :: [Fixed a] -> Value # toEncodingList :: [Fixed a] -> Encoding #
ToJSON a => ToJSON (Dual a)
Methods toJSON :: Dual a -> Value # toEncoding :: Dual a -> Encoding # toJSONList :: [Dual a] -> Value # toEncodingList :: [Dual a] -> Encoding #
ToJSON a => ToJSON (First a)
Methods toJSON :: First a -> Value # toEncoding :: First a -> Encoding # toJSONList :: [First a] -> Value # toEncodingList :: [First a] -> Encoding #
ToJSON a => ToJSON (Last a)
Methods toJSON :: Last a -> Value # toEncoding :: Last a -> Encoding # toJSONList :: [Last a] -> Value # toEncodingList :: [Last a] -> Encoding #
ToJSON a => ToJSON (IntMap a)
Methods toJSON :: IntMap a -> Value # toEncoding :: IntMap a -> Encoding # toJSONList :: [IntMap a] -> Value # toEncodingList :: [IntMap a] -> Encoding #
ToJSON v => ToJSON (Tree v)
Methods toJSON :: Tree v -> Value # toEncoding :: Tree v -> Encoding # toJSONList :: [Tree v] -> Value # toEncodingList :: [Tree v] -> Encoding #
ToJSON a => ToJSON (Seq a)
Methods toJSON :: Seq a -> Value # toEncoding :: Seq a -> Encoding # toJSONList :: [Seq a] -> Value # toEncodingList :: [Seq a] -> Encoding #
ToJSON a => ToJSON (Set a)
Methods toJSON :: Set a -> Value # toEncoding :: Set a -> Encoding # toJSONList :: [Set a] -> Value # toEncodingList :: [Set a] -> Encoding #
ToJSON a => ToJSON (DList a)
Methods toJSON :: DList a -> Value # toEncoding :: DList a -> Encoding # toJSONList :: [DList a] -> Value # toEncodingList :: [DList a] -> Encoding #
ToJSON a => ToJSON (HashSet a)
Methods toJSON :: HashSet a -> Value # toEncoding :: HashSet a -> Encoding # toJSONList :: [HashSet a] -> Value # toEncodingList :: [HashSet a] -> Encoding #
ToJSON a => ToJSON (Vector a)
Methods toJSON :: Vector a -> Value # toEncoding :: Vector a -> Encoding # toJSONList :: [Vector a] -> Value # toEncodingList :: [Vector a] -> Encoding #
(Storable a, ToJSON a) => ToJSON (Vector a)
Methods toJSON :: Vector a -> Value # toEncoding :: Vector a -> Encoding # toJSONList :: [Vector a] -> Value # toEncodingList :: [Vector a] -> Encoding #
(Vector Vector a, ToJSON a) => ToJSON (Vector a)
Methods toJSON :: Vector a -> Value # toEncoding :: Vector a -> Encoding # toJSONList :: [Vector a] -> Value # toEncodingList :: [Vector a] -> Encoding #
(Prim a, ToJSON a) => ToJSON (Vector a)
Methods toJSON :: Vector a -> Value # toEncoding :: Vector a -> Encoding # toJSONList :: [Vector a] -> Value # toEncodingList :: [Vector a] -> Encoding #
(ToJSON a, ToJSON b) => ToJSON (Either a b)
Methods toJSON :: Either a b -> Value # toEncoding :: Either a b -> Encoding # toJSONList :: [Either a b] -> Value # toEncodingList :: [Either a b] -> Encoding #
(ToJSON a, ToJSON b) => ToJSON (a, b)
Methods toJSON :: (a, b) -> Value # toEncoding :: (a, b) -> Encoding # toJSONList :: [(a, b)] -> Value # toEncodingList :: [(a, b)] -> Encoding #
(ToJSON v, ToJSONKey k) => ToJSON (HashMap k v)
Methods toJSON :: HashMap k v -> Value # toEncoding :: HashMap k v -> Encoding # toJSONList :: [HashMap k v] -> Value # toEncodingList :: [HashMap k v] -> Encoding #
(ToJSON v, ToJSONKey k) => ToJSON (Map k v)
Methods toJSON :: Map k v -> Value # toEncoding :: Map k v -> Encoding # toJSONList :: [Map k v] -> Value # toEncodingList :: [Map k v] -> Encoding #
ToJSON (Proxy k a)
Methods toJSON :: Proxy k a -> Value # toEncoding :: Proxy k a -> Encoding # toJSONList :: [Proxy k a] -> Value # toEncodingList :: [Proxy k a] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c) => ToJSON (a, b, c)
Methods toJSON :: (a, b, c) -> Value # toEncoding :: (a, b, c) -> Encoding # toJSONList :: [(a, b, c)] -> Value # toEncodingList :: [(a, b, c)] -> Encoding #
ToJSON a => ToJSON (Const k a b)
Methods toJSON :: Const k a b -> Value # toEncoding :: Const k a b -> Encoding # toJSONList :: [Const k a b] -> Value # toEncodingList :: [Const k a b] -> Encoding #
ToJSON b => ToJSON (Tagged k a b)
Methods toJSON :: Tagged k a b -> Value # toEncoding :: Tagged k a b -> Encoding # toJSONList :: [Tagged k a b] -> Value # toEncodingList :: [Tagged k a b] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON (a, b, c, d)
Methods toJSON :: (a, b, c, d) -> Value # toEncoding :: (a, b, c, d) -> Encoding # toJSONList :: [(a, b, c, d)] -> Value # toEncodingList :: [(a, b, c, d)] -> Encoding #
(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Sum * f g a)
Methods toJSON :: Sum * f g a -> Value # toEncoding :: Sum * f g a -> Encoding # toJSONList :: [Sum * f g a] -> Value # toEncodingList :: [Sum * f g a] -> Encoding #
(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Product * f g a)
Methods toJSON :: Product * f g a -> Value # toEncoding :: Product * f g a -> Encoding # toJSONList :: [Product * f g a] -> Value # toEncodingList :: [Product * f g a] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON (a, b, c, d, e)
Methods toJSON :: (a, b, c, d, e) -> Value # toEncoding :: (a, b, c, d, e) -> Encoding # toJSONList :: [(a, b, c, d, e)] -> Value # toEncodingList :: [(a, b, c, d, e)] -> Encoding #
(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Compose * * f g a)
Methods toJSON :: Compose * * f g a -> Value # toEncoding :: Compose * * f g a -> Encoding # toJSONList :: [Compose * * f g a] -> Value # toEncodingList :: [Compose * * f g a] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON (a, b, c, d, e, f)
Methods toJSON :: (a, b, c, d, e, f) -> Value # toEncoding :: (a, b, c, d, e, f) -> Encoding # toJSONList :: [(a, b, c, d, e, f)] -> Value # toEncodingList :: [(a, b, c, d, e, f)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON (a, b, c, d, e, f, g)
Methods toJSON :: (a, b, c, d, e, f, g) -> Value # toEncoding :: (a, b, c, d, e, f, g) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h) => ToJSON (a, b, c, d, e, f, g, h)
Methods toJSON :: (a, b, c, d, e, f, g, h) -> Value # toEncoding :: (a, b, c, d, e, f, g, h) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i) => ToJSON (a, b, c, d, e, f, g, h, i)
Methods toJSON :: (a, b, c, d, e, f, g, h, i) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j) => ToJSON (a, b, c, d, e, f, g, h, i, j)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k) => ToJSON (a, b, c, d, e, f, g, h, i, j, k)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j, k) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j, k) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m, ToJSON n) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> Encoding #
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l, ToJSON m, ToJSON n, ToJSON o) => ToJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
Methods toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Value # toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Encoding # toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> Value # toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> Encoding #

class FromJSON a where #

A type that can be converted from JSON, with the possibility of failure.

In many cases, you can get the compiler to generate parsing code for you (see below). To begin, let's cover writing an instance by hand.

There are various reasons a conversion could fail. For example, an Object could be missing a required key, an Array could be of the wrong size, or a value could be of an incompatible type.

The basic ways to signal a failed conversion are as follows:

empty and mzero work, but are terse and uninformative;
fail yields a custom error message;
typeMismatch produces an informative message for cases when the value encountered is not of the expected type.

An example type and instance using typeMismatch:

-- Allow ourselves to write Text literals.
{-# LANGUAGE OverloadedStrings #-}

data Coord = Coord { x :: Double, y :: Double }

instance FromJSON Coord where
    parseJSON (Object v) = Coord
        <$> v .: "x"
        <*> v .: "y"

    -- We do not expect a non-Object value here.
    -- We could use mzero to fail, but typeMismatch
    -- gives a much more informative error message.
    parseJSON invalid    = typeMismatch "Coord" invalid

For this common case of only being concerned with a single type of JSON value, the functions withObject, withNumber, etc. are provided. Their use is to be preferred when possible, since they are more terse. Using withObject, we can rewrite the above instance (assuming the same language extension and data type) as:

instance FromJSON Coord where
    parseJSON = withObject "Coord" $ v -> Coord
        <$> v .: "x"
        <*> v .: "y"

Instead of manually writing your FromJSON instance, there are two options to do it automatically:

Data.Aeson.TH provides Template Haskell functions which will derive an instance at compile time. The generated instance is optimized for your type so it will probably be more efficient than the following option.
The compiler can provide a default generic implementation for parseJSON.

To use the second, simply add a deriving Generic clause to your datatype and declare a FromJSON instance for your datatype without giving a definition for parseJSON.

For example, the previous example can be simplified to just:

{-# LANGUAGE DeriveGeneric #-}

import GHC.Generics

data Coord = Coord { x :: Double, y :: Double } deriving Generic

instance FromJSON Coord

The default implementation will be equivalent to parseJSON = genericParseJSON defaultOptions; If you need different options, you can customize the generic decoding by defining:

customOptions = defaultOptions
                { fieldLabelModifier = map toUpper
                }

instance FromJSON Coord where
    parseJSON = genericParseJSON customOptions

Methods

parseJSON :: Value -> Parser a #

parseJSONList :: Value -> Parser [a] #

Instances

FromJSON Bool
Methods parseJSON :: Value -> Parser Bool # parseJSONList :: Value -> Parser [Bool] #
FromJSON Char
Methods parseJSON :: Value -> Parser Char # parseJSONList :: Value -> Parser [Char] #
FromJSON Double
Methods parseJSON :: Value -> Parser Double # parseJSONList :: Value -> Parser [Double] #
FromJSON Float
Methods parseJSON :: Value -> Parser Float # parseJSONList :: Value -> Parser [Float] #
FromJSON Int
Methods parseJSON :: Value -> Parser Int # parseJSONList :: Value -> Parser [Int] #
FromJSON Int8
Methods parseJSON :: Value -> Parser Int8 # parseJSONList :: Value -> Parser [Int8] #
FromJSON Int16
Methods parseJSON :: Value -> Parser Int16 # parseJSONList :: Value -> Parser [Int16] #
FromJSON Int32
Methods parseJSON :: Value -> Parser Int32 # parseJSONList :: Value -> Parser [Int32] #
FromJSON Int64
Methods parseJSON :: Value -> Parser Int64 # parseJSONList :: Value -> Parser [Int64] #
FromJSON Integer	WARNING: Only parse Integers from trusted input since an attacker could easily fill up the memory of the target system by specifying a scientific number with a big exponent like `1e1000000000`.
Methods parseJSON :: Value -> Parser Integer # parseJSONList :: Value -> Parser [Integer] #
FromJSON Ordering
Methods parseJSON :: Value -> Parser Ordering # parseJSONList :: Value -> Parser [Ordering] #
FromJSON Word
Methods parseJSON :: Value -> Parser Word # parseJSONList :: Value -> Parser [Word] #
FromJSON Word8
Methods parseJSON :: Value -> Parser Word8 # parseJSONList :: Value -> Parser [Word8] #
FromJSON Word16
Methods parseJSON :: Value -> Parser Word16 # parseJSONList :: Value -> Parser [Word16] #
FromJSON Word32
Methods parseJSON :: Value -> Parser Word32 # parseJSONList :: Value -> Parser [Word32] #
FromJSON Word64
Methods parseJSON :: Value -> Parser Word64 # parseJSONList :: Value -> Parser [Word64] #
FromJSON ()
Methods parseJSON :: Value -> Parser () # parseJSONList :: Value -> Parser [()] #
FromJSON Scientific
Methods parseJSON :: Value -> Parser Scientific # parseJSONList :: Value -> Parser [Scientific] #
FromJSON Number
Methods parseJSON :: Value -> Parser Number # parseJSONList :: Value -> Parser [Number] #
FromJSON Text
Methods parseJSON :: Value -> Parser Text # parseJSONList :: Value -> Parser [Text] #
FromJSON UTCTime
Methods parseJSON :: Value -> Parser UTCTime # parseJSONList :: Value -> Parser [UTCTime] #
FromJSON Value
Methods parseJSON :: Value -> Parser Value # parseJSONList :: Value -> Parser [Value] #
FromJSON DotNetTime
Methods parseJSON :: Value -> Parser DotNetTime # parseJSONList :: Value -> Parser [DotNetTime] #
FromJSON Text
Methods parseJSON :: Value -> Parser Text # parseJSONList :: Value -> Parser [Text] #
FromJSON Natural
Methods parseJSON :: Value -> Parser Natural # parseJSONList :: Value -> Parser [Natural] #
FromJSON Version
Methods parseJSON :: Value -> Parser Version # parseJSONList :: Value -> Parser [Version] #
FromJSON IntSet
Methods parseJSON :: Value -> Parser IntSet # parseJSONList :: Value -> Parser [IntSet] #
FromJSON LocalTime
Methods parseJSON :: Value -> Parser LocalTime # parseJSONList :: Value -> Parser [LocalTime] #
FromJSON ZonedTime
Methods parseJSON :: Value -> Parser ZonedTime # parseJSONList :: Value -> Parser [ZonedTime] #
FromJSON TimeOfDay
Methods parseJSON :: Value -> Parser TimeOfDay # parseJSONList :: Value -> Parser [TimeOfDay] #
FromJSON NominalDiffTime	WARNING: Only parse lengths of time from trusted input since an attacker could easily fill up the memory of the target system by specifying a scientific number with a big exponent like `1e1000000000`.
Methods parseJSON :: Value -> Parser NominalDiffTime # parseJSONList :: Value -> Parser [NominalDiffTime] #
FromJSON Day
Methods parseJSON :: Value -> Parser Day # parseJSONList :: Value -> Parser [Day] #
FromJSON UUID
Methods parseJSON :: Value -> Parser UUID # parseJSONList :: Value -> Parser [UUID] #
FromJSON a => FromJSON [a]
Methods parseJSON :: Value -> Parser [a] # parseJSONList :: Value -> Parser [[a]] #
FromJSON a => FromJSON (Maybe a)
Methods parseJSON :: Value -> Parser (Maybe a) # parseJSONList :: Value -> Parser [Maybe a] #
(FromJSON a, Integral a) => FromJSON (Ratio a)
Methods parseJSON :: Value -> Parser (Ratio a) # parseJSONList :: Value -> Parser [Ratio a] #
FromJSON a => FromJSON (Identity a)
Methods parseJSON :: Value -> Parser (Identity a) # parseJSONList :: Value -> Parser [Identity a] #
FromJSON a => FromJSON (Min a)
Methods parseJSON :: Value -> Parser (Min a) # parseJSONList :: Value -> Parser [Min a] #
FromJSON a => FromJSON (Max a)
Methods parseJSON :: Value -> Parser (Max a) # parseJSONList :: Value -> Parser [Max a] #
FromJSON a => FromJSON (First a)
Methods parseJSON :: Value -> Parser (First a) # parseJSONList :: Value -> Parser [First a] #
FromJSON a => FromJSON (Last a)
Methods parseJSON :: Value -> Parser (Last a) # parseJSONList :: Value -> Parser [Last a] #
FromJSON a => FromJSON (WrappedMonoid a)
Methods parseJSON :: Value -> Parser (WrappedMonoid a) # parseJSONList :: Value -> Parser [WrappedMonoid a] #
FromJSON a => FromJSON (Option a)
Methods parseJSON :: Value -> Parser (Option a) # parseJSONList :: Value -> Parser [Option a] #
FromJSON a => FromJSON (NonEmpty a)
Methods parseJSON :: Value -> Parser (NonEmpty a) # parseJSONList :: Value -> Parser [NonEmpty a] #
HasResolution a => FromJSON (Fixed a)	WARNING: Only parse fixed-precision numbers from trusted input since an attacker could easily fill up the memory of the target system by specifying a scientific number with a big exponent like `1e1000000000`.
Methods parseJSON :: Value -> Parser (Fixed a) # parseJSONList :: Value -> Parser [Fixed a] #
FromJSON a => FromJSON (Dual a)
Methods parseJSON :: Value -> Parser (Dual a) # parseJSONList :: Value -> Parser [Dual a] #
FromJSON a => FromJSON (First a)
Methods parseJSON :: Value -> Parser (First a) # parseJSONList :: Value -> Parser [First a] #
FromJSON a => FromJSON (Last a)
Methods parseJSON :: Value -> Parser (Last a) # parseJSONList :: Value -> Parser [Last a] #
FromJSON a => FromJSON (IntMap a)
Methods parseJSON :: Value -> Parser (IntMap a) # parseJSONList :: Value -> Parser [IntMap a] #
FromJSON v => FromJSON (Tree v)
Methods parseJSON :: Value -> Parser (Tree v) # parseJSONList :: Value -> Parser [Tree v] #
FromJSON a => FromJSON (Seq a)
Methods parseJSON :: Value -> Parser (Seq a) # parseJSONList :: Value -> Parser [Seq a] #
(Ord a, FromJSON a) => FromJSON (Set a)
Methods parseJSON :: Value -> Parser (Set a) # parseJSONList :: Value -> Parser [Set a] #
FromJSON a => FromJSON (DList a)
Methods parseJSON :: Value -> Parser (DList a) # parseJSONList :: Value -> Parser [DList a] #
(Eq a, Hashable a, FromJSON a) => FromJSON (HashSet a)
Methods parseJSON :: Value -> Parser (HashSet a) # parseJSONList :: Value -> Parser [HashSet a] #
FromJSON a => FromJSON (Vector a)
Methods parseJSON :: Value -> Parser (Vector a) # parseJSONList :: Value -> Parser [Vector a] #
(Storable a, FromJSON a) => FromJSON (Vector a)
Methods parseJSON :: Value -> Parser (Vector a) # parseJSONList :: Value -> Parser [Vector a] #
(Vector Vector a, FromJSON a) => FromJSON (Vector a)
Methods parseJSON :: Value -> Parser (Vector a) # parseJSONList :: Value -> Parser [Vector a] #
(Prim a, FromJSON a) => FromJSON (Vector a)
Methods parseJSON :: Value -> Parser (Vector a) # parseJSONList :: Value -> Parser [Vector a] #
(FromJSON a, FromJSON b) => FromJSON (Either a b)
Methods parseJSON :: Value -> Parser (Either a b) # parseJSONList :: Value -> Parser [Either a b] #
(FromJSON a, FromJSON b) => FromJSON (a, b)
Methods parseJSON :: Value -> Parser (a, b) # parseJSONList :: Value -> Parser [(a, b)] #
(FromJSON v, FromJSONKey k, Eq k, Hashable k) => FromJSON (HashMap k v)
Methods parseJSON :: Value -> Parser (HashMap k v) # parseJSONList :: Value -> Parser [HashMap k v] #
(FromJSONKey k, Ord k, FromJSON v) => FromJSON (Map k v)
Methods parseJSON :: Value -> Parser (Map k v) # parseJSONList :: Value -> Parser [Map k v] #
FromJSON (Proxy k a)
Methods parseJSON :: Value -> Parser (Proxy k a) # parseJSONList :: Value -> Parser [Proxy k a] #
(FromJSON a, FromJSON b, FromJSON c) => FromJSON (a, b, c)
Methods parseJSON :: Value -> Parser (a, b, c) # parseJSONList :: Value -> Parser [(a, b, c)] #
FromJSON a => FromJSON (Const k a b)
Methods parseJSON :: Value -> Parser (Const k a b) # parseJSONList :: Value -> Parser [Const k a b] #
FromJSON b => FromJSON (Tagged k a b)
Methods parseJSON :: Value -> Parser (Tagged k a b) # parseJSONList :: Value -> Parser [Tagged k a b] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON (a, b, c, d)
Methods parseJSON :: Value -> Parser (a, b, c, d) # parseJSONList :: Value -> Parser [(a, b, c, d)] #
(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Sum * f g a)
Methods parseJSON :: Value -> Parser (Sum * f g a) # parseJSONList :: Value -> Parser [Sum * f g a] #
(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Product * f g a)
Methods parseJSON :: Value -> Parser (Product * f g a) # parseJSONList :: Value -> Parser [Product * f g a] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON (a, b, c, d, e)
Methods parseJSON :: Value -> Parser (a, b, c, d, e) # parseJSONList :: Value -> Parser [(a, b, c, d, e)] #
(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Compose * * f g a)
Methods parseJSON :: Value -> Parser (Compose * * f g a) # parseJSONList :: Value -> Parser [Compose * * f g a] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON (a, b, c, d, e, f)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON (a, b, c, d, e, f, g)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h) => FromJSON (a, b, c, d, e, f, g, h)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i) => FromJSON (a, b, c, d, e, f, g, h, i)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j) => FromJSON (a, b, c, d, e, f, g, h, i, j)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k) => FromJSON (a, b, c, d, e, f, g, h, i, j, k)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m, FromJSON n) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] #
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l, FromJSON m, FromJSON n, FromJSON o) => FromJSON (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
Methods parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] #

data Proxy k t :: forall k. k -> * #

A concrete, poly-kinded proxy type

Constructors

Proxy

Instances

Monad (Proxy *)
Methods (>>=) :: Proxy * a -> (a -> Proxy * b) -> Proxy * b # (>>) :: Proxy * a -> Proxy * b -> Proxy * b # return :: a -> Proxy * a # fail :: String -> Proxy * a #
Functor (Proxy *)
Methods fmap :: (a -> b) -> Proxy * a -> Proxy * b # (<$) :: a -> Proxy * b -> Proxy * a #
Applicative (Proxy *)
Methods pure :: a -> Proxy * a # (<>) :: Proxy (a -> b) -> Proxy * a -> Proxy * b # (>) :: Proxy a -> Proxy * b -> Proxy * b # (<) :: Proxy a -> Proxy * b -> Proxy * a #
Foldable (Proxy *)
Methods fold :: Monoid m => Proxy * m -> m # foldMap :: Monoid m => (a -> m) -> Proxy * a -> m # foldr :: (a -> b -> b) -> b -> Proxy * a -> b # foldr' :: (a -> b -> b) -> b -> Proxy * a -> b # foldl :: (b -> a -> b) -> b -> Proxy * a -> b # foldl' :: (b -> a -> b) -> b -> Proxy * a -> b # foldr1 :: (a -> a -> a) -> Proxy * a -> a # foldl1 :: (a -> a -> a) -> Proxy * a -> a # toList :: Proxy * a -> [a] # null :: Proxy * a -> Bool # length :: Proxy * a -> Int # elem :: Eq a => a -> Proxy * a -> Bool # maximum :: Ord a => Proxy * a -> a # minimum :: Ord a => Proxy * a -> a # sum :: Num a => Proxy * a -> a # product :: Num a => Proxy * a -> a #
Generic1 (Proxy *)
Associated Types type Rep1 (Proxy * :: * -> ) :: -> * # Methods from1 :: Proxy * a -> Rep1 (Proxy ) a # to1 :: Rep1 (Proxy ) a -> Proxy * a #
ToJSON1 (Proxy *)
Methods liftToJSON :: (a -> Value) -> ([a] -> Value) -> Proxy * a -> Value # liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Proxy * a] -> Value # liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Proxy * a -> Encoding # liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Proxy * a] -> Encoding #
FromJSON1 (Proxy *)
Methods liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Proxy * a) # liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Proxy * a] #
Alternative (Proxy *)
Methods empty :: Proxy * a # (<\|>) :: Proxy * a -> Proxy * a -> Proxy * a # some :: Proxy * a -> Proxy * [a] # many :: Proxy * a -> Proxy * [a] #
MonadPlus (Proxy *)
Methods mzero :: Proxy * a # mplus :: Proxy * a -> Proxy * a -> Proxy * a #
Hashable1 (Proxy *)
Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Proxy * a -> Int #
Bounded (Proxy k s)
Methods minBound :: Proxy k s # maxBound :: Proxy k s #
Enum (Proxy k s)
Methods succ :: Proxy k s -> Proxy k s # pred :: Proxy k s -> Proxy k s # toEnum :: Int -> Proxy k s # fromEnum :: Proxy k s -> Int # enumFrom :: Proxy k s -> [Proxy k s] # enumFromThen :: Proxy k s -> Proxy k s -> [Proxy k s] # enumFromTo :: Proxy k s -> Proxy k s -> [Proxy k s] # enumFromThenTo :: Proxy k s -> Proxy k s -> Proxy k s -> [Proxy k s] #
Eq (Proxy k s)
Methods (==) :: Proxy k s -> Proxy k s -> Bool # (/=) :: Proxy k s -> Proxy k s -> Bool #
Data t => Data (Proxy * t)
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Proxy * t -> c (Proxy * t) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Proxy * t) # toConstr :: Proxy * t -> Constr # dataTypeOf :: Proxy * t -> DataType # dataCast1 :: Typeable (* -> ) t => (forall d. Data d => c (t d)) -> Maybe (c (Proxy t)) # dataCast2 :: Typeable (* -> * -> ) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Proxy t)) # gmapT :: (forall b. Data b => b -> b) -> Proxy * t -> Proxy * t # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Proxy * t -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Proxy * t -> r # gmapQ :: (forall d. Data d => d -> u) -> Proxy * t -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Proxy * t -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Proxy * t -> m (Proxy * t) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy * t -> m (Proxy * t) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy * t -> m (Proxy * t) #
Ord (Proxy k s)
Methods compare :: Proxy k s -> Proxy k s -> Ordering # (<) :: Proxy k s -> Proxy k s -> Bool # (<=) :: Proxy k s -> Proxy k s -> Bool # (>) :: Proxy k s -> Proxy k s -> Bool # (>=) :: Proxy k s -> Proxy k s -> Bool # max :: Proxy k s -> Proxy k s -> Proxy k s # min :: Proxy k s -> Proxy k s -> Proxy k s #
Read (Proxy k s)
Methods readsPrec :: Int -> ReadS (Proxy k s) # readList :: ReadS [Proxy k s] # readPrec :: ReadPrec (Proxy k s) # readListPrec :: ReadPrec [Proxy k s] #
Show (Proxy k s)
Methods showsPrec :: Int -> Proxy k s -> ShowS # show :: Proxy k s -> String # showList :: [Proxy k s] -> ShowS #
Ix (Proxy k s)
Methods range :: (Proxy k s, Proxy k s) -> [Proxy k s] # index :: (Proxy k s, Proxy k s) -> Proxy k s -> Int # unsafeIndex :: (Proxy k s, Proxy k s) -> Proxy k s -> Int inRange :: (Proxy k s, Proxy k s) -> Proxy k s -> Bool # rangeSize :: (Proxy k s, Proxy k s) -> Int # unsafeRangeSize :: (Proxy k s, Proxy k s) -> Int
Generic (Proxy k t)
Associated Types type Rep (Proxy k t) :: * -> * # Methods from :: Proxy k t -> Rep (Proxy k t) x # to :: Rep (Proxy k t) x -> Proxy k t #
Monoid (Proxy k s)
Methods mempty :: Proxy k s # mappend :: Proxy k s -> Proxy k s -> Proxy k s # mconcat :: [Proxy k s] -> Proxy k s #
Hashable (Proxy * a)
Methods hashWithSalt :: Int -> Proxy * a -> Int # hash :: Proxy * a -> Int #
ToJSON (Proxy k a)
Methods toJSON :: Proxy k a -> Value # toEncoding :: Proxy k a -> Encoding # toJSONList :: [Proxy k a] -> Value # toEncodingList :: [Proxy k a] -> Encoding #
FromJSON (Proxy k a)
Methods parseJSON :: Value -> Parser (Proxy k a) # parseJSONList :: Value -> Parser [Proxy k a] #
type Rep1 (Proxy *)
type Rep1 (Proxy *) = D1 (MetaData "Proxy" "Data.Proxy" "base" False) (C1 (MetaCons "Proxy" PrefixI False) U1)
type Rep (Proxy k t)
type Rep (Proxy k t) = D1 (MetaData "Proxy" "Data.Proxy" "base" False) (C1 (MetaCons "Proxy" PrefixI False) U1)
type Code (Proxy * t0)
type Code (Proxy * t0) = (:) [] ([] ) ([] [*])