aeson-1.4.0.0: Fast JSON parsing and encoding

Copyright(c) 2011-2016 Bryan O'Sullivan
(c) 2011 MailRank Inc.
LicenseBSD3
MaintainerBryan O'Sullivan <bos@serpentine.com>
Stabilityexperimental
Portabilityportable
Safe HaskellNone
LanguageHaskell2010

Data.Aeson.Types

Contents

Description

Types for working with JSON data.

Synopsis

Core JSON types

data Value Source #

A JSON value represented as a Haskell value.

Instances

Eq Value Source # 

Methods

(==) :: Value -> Value -> Bool #

(/=) :: Value -> Value -> Bool #

Data Value Source # 

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Value -> c Value #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Value #

toConstr :: Value -> Constr #

dataTypeOf :: Value -> DataType #

dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c Value) #

dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Value) #

gmapT :: (forall b. Data b => b -> b) -> Value -> Value #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Value -> r #

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Value -> r #

gmapQ :: (forall d. Data d => d -> u) -> Value -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Value -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Value -> m Value #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Value -> m Value #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Value -> m Value #

Read Value Source # 
Show Value Source # 

Methods

showsPrec :: Int -> Value -> ShowS #

show :: Value -> String #

showList :: [Value] -> ShowS #

IsString Value Source # 

Methods

fromString :: String -> Value #

Generic Value Source # 

Associated Types

type Rep Value :: * -> * #

Methods

from :: Value -> Rep Value x #

to :: Rep Value x -> Value #

Lift Value Source # 

Methods

lift :: Value -> Q Exp #

NFData Value Source # 

Methods

rnf :: Value -> () #

Hashable Value Source # 

Methods

hashWithSalt :: Int -> Value -> Int #

hash :: Value -> Int #

FromJSON Value Source # 
KeyValue Pair Source # 

Methods

(.=) :: ToJSON v => Text -> v -> Pair Source #

ToJSON Value Source # 
type Rep Value Source # 

type Encoding = Encoding' Value Source #

Often used synonym for Encoding'.

unsafeToEncoding :: Builder -> Encoding' a Source #

Make Encoding from Builder.

Use with care! You have to make sure that the passed Builder is a valid JSON Encoding!

fromEncoding :: Encoding' tag -> Builder Source #

Acquire the underlying bytestring builder.

data Series Source #

A series of values that, when encoded, should be separated by commas. Since 0.11.0.0, the .= operator is overloaded to create either (Text, Value) or Series. You can use Series when encoding directly to a bytestring builder as in the following example:

toEncoding (Person name age) = pairs ("name" .= name <> "age" .= age)

type Array = Vector Value Source #

A JSON "array" (sequence).

emptyArray :: Value Source #

The empty array.

type Pair = (Text, Value) Source #

A key/value pair for an Object.

type Object = HashMap Text Value Source #

A JSON "object" (key/value map).

emptyObject :: Value Source #

The empty object.

Convenience types and functions

newtype DotNetTime Source #

A newtype wrapper for UTCTime that uses the same non-standard serialization format as Microsoft .NET, whose System.DateTime type is by default serialized to JSON as in the following example:

/Date(1302547608878)/

The number represents milliseconds since the Unix epoch.

Constructors

DotNetTime 

Fields

typeMismatch Source #

Arguments

:: String

The name of the type you are trying to parse.

-> Value

The actual value encountered.

-> Parser a 

Fail parsing due to a type mismatch, with a descriptive message.

Example usage:

instance FromJSON Coord where
  parseJSON (Object v) = {- type matches, life is good -}
  parseJSON wat        = typeMismatch "Coord" wat

Type conversion

data Parser a Source #

A JSON parser. N.B. This might not fit your usual understanding of "parser". Instead you might like to think of Parser as a "parse result", i.e. a parser to which the input has already been applied.

Instances

Monad Parser Source # 

Methods

(>>=) :: Parser a -> (a -> Parser b) -> Parser b #

(>>) :: Parser a -> Parser b -> Parser b #

return :: a -> Parser a #

fail :: String -> Parser a #

Functor Parser Source # 

Methods

fmap :: (a -> b) -> Parser a -> Parser b #

(<$) :: a -> Parser b -> Parser a #

MonadFail Parser Source # 

Methods

fail :: String -> Parser a #

Applicative Parser Source # 

Methods

pure :: a -> Parser a #

(<*>) :: Parser (a -> b) -> Parser a -> Parser b #

liftA2 :: (a -> b -> c) -> Parser a -> Parser b -> Parser c #

(*>) :: Parser a -> Parser b -> Parser b #

(<*) :: Parser a -> Parser b -> Parser a #

Alternative Parser Source # 

Methods

empty :: Parser a #

(<|>) :: Parser a -> Parser a -> Parser a #

some :: Parser a -> Parser [a] #

many :: Parser a -> Parser [a] #

MonadPlus Parser Source # 

Methods

mzero :: Parser a #

mplus :: Parser a -> Parser a -> Parser a #

Semigroup (Parser a) Source # 

Methods

(<>) :: Parser a -> Parser a -> Parser a #

sconcat :: NonEmpty (Parser a) -> Parser a #

stimes :: Integral b => b -> Parser a -> Parser a #

Monoid (Parser a) Source # 

Methods

mempty :: Parser a #

mappend :: Parser a -> Parser a -> Parser a #

mconcat :: [Parser a] -> Parser a #

data Result a Source #

The result of running a Parser.

Constructors

Error String 
Success a 

Instances

Monad Result Source # 

Methods

(>>=) :: Result a -> (a -> Result b) -> Result b #

(>>) :: Result a -> Result b -> Result b #

return :: a -> Result a #

fail :: String -> Result a #

Functor Result Source # 

Methods

fmap :: (a -> b) -> Result a -> Result b #

(<$) :: a -> Result b -> Result a #

MonadFail Result Source # 

Methods

fail :: String -> Result a #

Applicative Result Source # 

Methods

pure :: a -> Result a #

(<*>) :: Result (a -> b) -> Result a -> Result b #

liftA2 :: (a -> b -> c) -> Result a -> Result b -> Result c #

(*>) :: Result a -> Result b -> Result b #

(<*) :: Result a -> Result b -> Result a #

Foldable Result Source # 

Methods

fold :: Monoid m => Result m -> m #

foldMap :: Monoid m => (a -> m) -> Result a -> m #

foldr :: (a -> b -> b) -> b -> Result a -> b #

foldr' :: (a -> b -> b) -> b -> Result a -> b #

foldl :: (b -> a -> b) -> b -> Result a -> b #

foldl' :: (b -> a -> b) -> b -> Result a -> b #

foldr1 :: (a -> a -> a) -> Result a -> a #

foldl1 :: (a -> a -> a) -> Result a -> a #

toList :: Result a -> [a] #

null :: Result a -> Bool #

length :: Result a -> Int #

elem :: Eq a => a -> Result a -> Bool #

maximum :: Ord a => Result a -> a #

minimum :: Ord a => Result a -> a #

sum :: Num a => Result a -> a #

product :: Num a => Result a -> a #

Traversable Result Source # 

Methods

traverse :: Applicative f => (a -> f b) -> Result a -> f (Result b) #

sequenceA :: Applicative f => Result (f a) -> f (Result a) #

mapM :: Monad m => (a -> m b) -> Result a -> m (Result b) #

sequence :: Monad m => Result (m a) -> m (Result a) #

Alternative Result Source # 

Methods

empty :: Result a #

(<|>) :: Result a -> Result a -> Result a #

some :: Result a -> Result [a] #

many :: Result a -> Result [a] #

MonadPlus Result Source # 

Methods

mzero :: Result a #

mplus :: Result a -> Result a -> Result a #

Eq a => Eq (Result a) Source # 

Methods

(==) :: Result a -> Result a -> Bool #

(/=) :: Result a -> Result a -> Bool #

Show a => Show (Result a) Source # 

Methods

showsPrec :: Int -> Result a -> ShowS #

show :: Result a -> String #

showList :: [Result a] -> ShowS #

Semigroup (Result a) Source # 

Methods

(<>) :: Result a -> Result a -> Result a #

sconcat :: NonEmpty (Result a) -> Result a #

stimes :: Integral b => b -> Result a -> Result a #

Monoid (Result a) Source # 

Methods

mempty :: Result a #

mappend :: Result a -> Result a -> Result a #

mconcat :: [Result a] -> Result a #

NFData a => NFData (Result a) Source # 

Methods

rnf :: Result a -> () #

class FromJSON a where Source #

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

Instances

FromJSON Bool Source # 
FromJSON Char Source # 
FromJSON Double Source # 
FromJSON Float Source # 
FromJSON Int Source # 
FromJSON Int8 Source # 
FromJSON Int16 Source # 
FromJSON Int32 Source # 
FromJSON Int64 Source # 
FromJSON Integer Source #

This instance includes a bounds check to prevent maliciously large inputs to fill up the memory of the target system. You can newtype Scientific and provide your own instance using withScientific if you want to allow larger inputs.

FromJSON Natural Source # 
FromJSON Ordering Source # 
FromJSON Word Source # 
FromJSON Word8 Source # 
FromJSON Word16 Source # 
FromJSON Word32 Source # 
FromJSON Word64 Source # 
FromJSON () Source # 
FromJSON Text Source # 
FromJSON Text Source # 
FromJSON Version Source # 
FromJSON CTime Source # 
FromJSON IntSet Source # 
FromJSON Scientific Source # 
FromJSON ZonedTime Source #

Supported string formats:

YYYY-MM-DD HH:MM Z YYYY-MM-DD HH:MM:SS Z YYYY-MM-DD HH:MM:SS.SSS Z

The first space may instead be a T, and the second space is optional. The Z represents UTC. The Z may be replaced with a time zone offset of the form +0000 or -08:00, where the first two digits are hours, the : is optional and the second two digits (also optional) are minutes.

FromJSON LocalTime Source # 
FromJSON TimeOfDay Source # 
FromJSON UTCTime Source # 
FromJSON NominalDiffTime Source #

This instance includes a bounds check to prevent maliciously large inputs to fill up the memory of the target system. You can newtype Scientific and provide your own instance using withScientific if you want to allow larger inputs.

FromJSON DiffTime Source #

This instance includes a bounds check to prevent maliciously large inputs to fill up the memory of the target system. You can newtype Scientific and provide your own instance using withScientific if you want to allow larger inputs.

FromJSON Day Source # 
FromJSON UUID Source # 
FromJSON DotNetTime Source # 
FromJSON Value Source # 
FromJSON a => FromJSON [a] Source # 
FromJSON a => FromJSON (Maybe a) Source # 
(FromJSON a, Integral a) => FromJSON (Ratio a) Source # 
HasResolution a => FromJSON (Fixed a) Source #

This instance includes a bounds check to prevent maliciously large inputs to fill up the memory of the target system. You can newtype Scientific and provide your own instance using withScientific if you want to allow larger inputs.

FromJSON a => FromJSON (Min a) Source # 
FromJSON a => FromJSON (Max a) Source # 
FromJSON a => FromJSON (First a) Source # 
FromJSON a => FromJSON (Last a) Source # 
FromJSON a => FromJSON (WrappedMonoid a) Source # 
FromJSON a => FromJSON (Option a) Source # 
FromJSON a => FromJSON (NonEmpty a) Source # 
FromJSON a => FromJSON (Identity a) Source # 
FromJSON a => FromJSON (Dual a) Source # 
FromJSON a => FromJSON (First a) Source # 
FromJSON a => FromJSON (Last a) Source # 
FromJSON a => FromJSON (IntMap a) Source # 
FromJSON v => FromJSON (Tree v) Source # 
FromJSON a => FromJSON (Seq a) Source # 
(Ord a, FromJSON a) => FromJSON (Set a) Source # 
FromJSON a => FromJSON (DList a) Source # 
(Eq a, Hashable a, FromJSON a) => FromJSON (HashSet a) Source # 
(Vector Vector a, FromJSON a) => FromJSON (Vector a) Source # 
(Storable a, FromJSON a) => FromJSON (Vector a) Source # 
(Prim a, FromJSON a) => FromJSON (Vector a) Source # 
FromJSON a => FromJSON (Vector a) Source # 
(FromJSON a, FromJSON b) => FromJSON (Either a b) Source # 
(FromJSON a, FromJSON b) => FromJSON (a, b) Source # 

Methods

parseJSON :: Value -> Parser (a, b) Source #

parseJSONList :: Value -> Parser [(a, b)] Source #

FromJSON (Proxy k a) Source # 
(FromJSONKey k, Ord k, FromJSON v) => FromJSON (Map k v) Source # 
(FromJSON v, FromJSONKey k, Eq k, Hashable k) => FromJSON (HashMap k v) Source # 
(FromJSON a, FromJSON b, FromJSON c) => FromJSON (a, b, c) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c) Source #

parseJSONList :: Value -> Parser [(a, b, c)] Source #

FromJSON a => FromJSON (Const k a b) Source # 
FromJSON b => FromJSON (Tagged k a b) Source # 
(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON (a, b, c, d) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d) Source #

parseJSONList :: Value -> Parser [(a, b, c, d)] Source #

(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Product * f g a) Source # 
(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Sum * f g a) Source # 

Methods

parseJSON :: Value -> Parser (Sum * f g a) Source #

parseJSONList :: Value -> Parser [Sum * f g a] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON (a, b, c, d, e) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e)] Source #

(FromJSON1 f, FromJSON1 g, FromJSON a) => FromJSON (Compose * * f g a) Source # 
(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON (a, b, c, d, e, f) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON (a, b, c, d, e, f, g) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, n) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] Source #

(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) Source # 

Methods

parseJSON :: Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) Source #

parseJSONList :: Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] Source #

fromJSON :: FromJSON a => Value -> Result a Source #

Convert a value from JSON, failing if the types do not match.

parse :: (a -> Parser b) -> a -> Result b Source #

Run a Parser.

parseEither :: (a -> Parser b) -> a -> Either String b Source #

Run a Parser with an Either result type. If the parse fails, the Left payload will contain an error message.

parseMaybe :: (a -> Parser b) -> a -> Maybe b Source #

Run a Parser with a Maybe result type.

class ToJSON a where Source #

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:

  1. 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.
  2. 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 Source #

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

toJSON :: (Generic a, GToJSON Value Zero (Rep a)) => a -> Value Source #

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

toEncoding :: a -> Encoding Source #

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 Source #

toEncodingList :: [a] -> Encoding Source #

Instances

ToJSON Bool Source # 
ToJSON Char Source # 
ToJSON Double Source # 
ToJSON Float Source # 
ToJSON Int Source # 
ToJSON Int8 Source # 
ToJSON Int16 Source # 
ToJSON Int32 Source # 
ToJSON Int64 Source # 
ToJSON Integer Source # 
ToJSON Natural Source # 
ToJSON Ordering Source # 
ToJSON Word Source # 
ToJSON Word8 Source # 
ToJSON Word16 Source # 
ToJSON Word32 Source # 
ToJSON Word64 Source # 
ToJSON () Source # 
ToJSON Text Source # 
ToJSON Text Source # 
ToJSON Number Source # 
ToJSON Version Source # 
ToJSON CTime Source # 
ToJSON IntSet Source # 
ToJSON Scientific Source # 
ToJSON ZonedTime Source # 
ToJSON LocalTime Source # 
ToJSON TimeOfDay Source # 
ToJSON UTCTime Source # 
ToJSON NominalDiffTime Source # 
ToJSON DiffTime Source # 
ToJSON Day Source # 
ToJSON UUID Source # 
ToJSON DotNetTime Source # 
ToJSON Value Source # 
ToJSON a => ToJSON [a] Source # 

Methods

toJSON :: [a] -> Value Source #

toEncoding :: [a] -> Encoding Source #

toJSONList :: [[a]] -> Value Source #

toEncodingList :: [[a]] -> Encoding Source #

ToJSON a => ToJSON (Maybe a) Source # 
(ToJSON a, Integral a) => ToJSON (Ratio a) Source # 
HasResolution a => ToJSON (Fixed a) Source # 
ToJSON a => ToJSON (Min a) Source # 
ToJSON a => ToJSON (Max a) Source # 
ToJSON a => ToJSON (First a) Source # 
ToJSON a => ToJSON (Last a) Source # 
ToJSON a => ToJSON (WrappedMonoid a) Source # 
ToJSON a => ToJSON (Option a) Source # 
ToJSON a => ToJSON (NonEmpty a) Source # 
ToJSON a => ToJSON (Identity a) Source # 
ToJSON a => ToJSON (Dual a) Source # 
ToJSON a => ToJSON (First a) Source # 
ToJSON a => ToJSON (Last a) Source # 
ToJSON a => ToJSON (IntMap a) Source # 
ToJSON v => ToJSON (Tree v) Source # 
ToJSON a => ToJSON (Seq a) Source # 
ToJSON a => ToJSON (Set a) Source # 
ToJSON a => ToJSON (DList a) Source # 
ToJSON a => ToJSON (HashSet a) Source # 
(Vector Vector a, ToJSON a) => ToJSON (Vector a) Source # 
(Storable a, ToJSON a) => ToJSON (Vector a) Source # 
(Prim a, ToJSON a) => ToJSON (Vector a) Source # 
ToJSON a => ToJSON (Vector a) Source # 
(ToJSON a, ToJSON b) => ToJSON (Either a b) Source # 
(ToJSON a, ToJSON b) => ToJSON (a, b) Source # 

Methods

toJSON :: (a, b) -> Value Source #

toEncoding :: (a, b) -> Encoding Source #

toJSONList :: [(a, b)] -> Value Source #

toEncodingList :: [(a, b)] -> Encoding Source #

ToJSON (Proxy k a) Source # 
(ToJSON v, ToJSONKey k) => ToJSON (Map k v) Source # 
(ToJSON v, ToJSONKey k) => ToJSON (HashMap k v) Source # 
(ToJSON a, ToJSON b, ToJSON c) => ToJSON (a, b, c) Source # 

Methods

toJSON :: (a, b, c) -> Value Source #

toEncoding :: (a, b, c) -> Encoding Source #

toJSONList :: [(a, b, c)] -> Value Source #

toEncodingList :: [(a, b, c)] -> Encoding Source #

ToJSON a => ToJSON (Const k a b) Source # 
ToJSON b => ToJSON (Tagged k a b) Source # 
(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON (a, b, c, d) Source # 

Methods

toJSON :: (a, b, c, d) -> Value Source #

toEncoding :: (a, b, c, d) -> Encoding Source #

toJSONList :: [(a, b, c, d)] -> Value Source #

toEncodingList :: [(a, b, c, d)] -> Encoding Source #

(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Product * f g a) Source # 
(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Sum * f g a) Source # 

Methods

toJSON :: Sum * f g a -> Value Source #

toEncoding :: Sum * f g a -> Encoding Source #

toJSONList :: [Sum * f g a] -> Value Source #

toEncodingList :: [Sum * f g a] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON (a, b, c, d, e) Source # 

Methods

toJSON :: (a, b, c, d, e) -> Value Source #

toEncoding :: (a, b, c, d, e) -> Encoding Source #

toJSONList :: [(a, b, c, d, e)] -> Value Source #

toEncodingList :: [(a, b, c, d, e)] -> Encoding Source #

(ToJSON1 f, ToJSON1 g, ToJSON a) => ToJSON (Compose * * f g a) Source # 
(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON (a, b, c, d, e, f) Source # 

Methods

toJSON :: (a, b, c, d, e, f) -> Value Source #

toEncoding :: (a, b, c, d, e, f) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON (a, b, c, d, e, f, g) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j, k) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j, k) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> Encoding Source #

(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) Source # 

Methods

toJSON :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Value Source #

toEncoding :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Encoding Source #

toJSONList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> Value Source #

toEncodingList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> Encoding Source #

class KeyValue kv where Source #

A key-value pair for encoding a JSON object.

Minimal complete definition

(.=)

Methods

(.=) :: ToJSON v => Text -> v -> kv infixr 8 Source #

Instances

KeyValue Pair Source # 

Methods

(.=) :: ToJSON v => Text -> v -> Pair Source #

KeyValue Series Source # 

Methods

(.=) :: ToJSON v => Text -> v -> Series Source #

modifyFailure :: (String -> String) -> Parser a -> Parser a Source #

If the inner Parser failed, modify the failure message using the provided function. This allows you to create more descriptive error messages. For example:

parseJSON (Object o) = modifyFailure
    ("Parsing of the Foo value failed: " ++)
    (Foo <$> o .: "someField")

Since 0.6.2.0

parserThrowError :: JSONPath -> String -> Parser a Source #

Throw a parser error with an additional path.

Since: 1.2.1.0

parserCatchError :: Parser a -> (JSONPath -> String -> Parser a) -> Parser a Source #

A handler function to handle previous errors and return to normal execution.

Since: 1.2.1.0

Keys for maps

class ToJSONKey a where Source #

Typeclass for types that can be used as the key of a map-like container (like Map or HashMap). For example, since Text has a ToJSONKey instance and Char has a ToJSON instance, we can encode a value of type Map Text Char:

>>> LBC8.putStrLn $ encode $ Map.fromList [("foo" :: Text, 'a')]
{"foo":"a"}

Since Int also has a ToJSONKey instance, we can similarly write:

>>> LBC8.putStrLn $ encode $ Map.fromList [(5 :: Int, 'a')]
{"5":"a"}

JSON documents only accept strings as object keys. For any type from base that has a natural textual representation, it can be expected that its ToJSONKey instance will choose that representation.

For data types that lack a natural textual representation, an alternative is provided. The map-like container is represented as a JSON array instead of a JSON object. Each value in the array is an array with exactly two values. The first is the key and the second is the value.

For example, values of type '[Text]' cannot be encoded to a string, so a Map with keys of type '[Text]' is encoded as follows:

>>> LBC8.putStrLn $ encode $ Map.fromList [(["foo","bar","baz" :: Text], 'a')]
[[["foo","bar","baz"],"a"]]

The default implementation of ToJSONKey chooses this method of encoding a key, using the ToJSON instance of the type.

To use your own data type as the key in a map, all that is needed is to write a ToJSONKey (and possibly a FromJSONKey) instance for it. If the type cannot be trivially converted to and from Text, it is recommended that ToJSONKeyValue is used. Since the default implementations of the typeclass methods can build this from a ToJSON instance, there is nothing that needs to be written:

data Foo = Foo { fooAge :: Int, fooName :: Text }
  deriving (Eq,Ord,Generic)
instance ToJSON Foo
instance ToJSONKey Foo

That's it. We can now write:

>>> let m = Map.fromList [(Foo 4 "bar",'a'),(Foo 6 "arg",'b')]
>>> LBC8.putStrLn $ encode m
[[{"fooName":"bar","fooAge":4},"a"],[{"fooName":"arg","fooAge":6},"b"]]

The next case to consider is if we have a type that is a newtype wrapper around Text. The recommended approach is to use generalized newtype deriving:

newtype RecordId = RecordId { getRecordId :: Text}
  deriving (Eq,Ord,ToJSONKey)

Then we may write:

>>> LBC8.putStrLn $ encode $ Map.fromList [(RecordId "abc",'a')]
{"abc":"a"}

Simple sum types are a final case worth considering. Suppose we have:

data Color = Red | Green | Blue
  deriving (Show,Read,Eq,Ord)

It is possible to get the ToJSONKey instance for free as we did with Foo. However, in this case, we have a natural way to go to and from Text that does not require any escape sequences. So, in this example, ToJSONKeyText will be used instead of ToJSONKeyValue. The Show instance can be used to help write ToJSONKey:

instance ToJSONKey Color where
  toJSONKey = ToJSONKeyText f g
    where f = Text.pack . show
          g = text . Text.pack . show
          -- text function is from Data.Aeson.Encoding

The situation of needing to turning function a -> Text into a ToJSONKeyFunction is common enough that a special combinator is provided for it. The above instance can be rewritten as:

instance ToJSONKey Color where
  toJSONKey = toJSONKeyText (Text.pack . show)

The performance of the above instance can be improved by not using String as an intermediate step when converting to Text. One option for improving performance would be to use template haskell machinery from the text-show package. However, even with the approach, the Encoding (a wrapper around a bytestring builder) is generated by encoding the Text to a ByteString, an intermediate step that could be avoided. The fastest possible implementation would be:

-- Assuming that OverloadedStrings is enabled
instance ToJSONKey Color where
  toJSONKey = ToJSONKeyText f g
    where f x = case x of {Red -> "Red";Green ->"Green";Blue -> "Blue"}
          g x = case x of {Red -> text "Red";Green -> text "Green";Blue -> text "Blue"}
          -- text function is from Data.Aeson.Encoding

This works because GHC can lift the encoded values out of the case statements, which means that they are only evaluated once. This approach should only be used when there is a serious need to maximize performance.

Methods

toJSONKey :: ToJSONKeyFunction a Source #

Strategy for rendering the key for a map-like container.

toJSONKey :: ToJSON a => ToJSONKeyFunction a Source #

Strategy for rendering the key for a map-like container.

toJSONKeyList :: ToJSONKeyFunction [a] Source #

This is similar in spirit to the showsList method of Show. It makes it possible to give String keys special treatment without using OverlappingInstances. End users should always be able to use the default implementation of this method.

toJSONKeyList :: ToJSON a => ToJSONKeyFunction [a] Source #

This is similar in spirit to the showsList method of Show. It makes it possible to give String keys special treatment without using OverlappingInstances. End users should always be able to use the default implementation of this method.

Instances

ToJSONKey Bool Source # 
ToJSONKey Char Source # 
ToJSONKey Double Source # 
ToJSONKey Float Source # 
ToJSONKey Int Source # 
ToJSONKey Int8 Source # 
ToJSONKey Int16 Source # 
ToJSONKey Int32 Source # 
ToJSONKey Int64 Source # 
ToJSONKey Integer Source # 
ToJSONKey Natural Source # 
ToJSONKey Word Source # 
ToJSONKey Word8 Source # 
ToJSONKey Word16 Source # 
ToJSONKey Word32 Source # 
ToJSONKey Word64 Source # 
ToJSONKey Text Source # 
ToJSONKey Text Source # 
ToJSONKey Version Source # 
ToJSONKey Scientific Source # 
ToJSONKey ZonedTime Source # 
ToJSONKey LocalTime Source # 
ToJSONKey TimeOfDay Source # 
ToJSONKey UTCTime Source # 
ToJSONKey Day Source # 
ToJSONKey UUID Source # 
(ToJSONKey a, ToJSON a) => ToJSONKey [a] Source # 
HasResolution a => ToJSONKey (Fixed a) Source # 
ToJSONKey a => ToJSONKey (Identity a) Source # 
(ToJSON a, ToJSON b) => ToJSONKey (a, b) Source # 
(ToJSON a, ToJSON b, ToJSON c) => ToJSONKey (a, b, c) Source # 
ToJSONKey b => ToJSONKey (Tagged k a b) Source # 
(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSONKey (a, b, c, d) Source # 

Methods

toJSONKey :: ToJSONKeyFunction (a, b, c, d) Source #

toJSONKeyList :: ToJSONKeyFunction [(a, b, c, d)] Source #

data ToJSONKeyFunction a Source #

Constructors

ToJSONKeyText !(a -> Text) !(a -> Encoding' Text)

key is encoded to string, produces object

ToJSONKeyValue !(a -> Value) !(a -> Encoding)

key is encoded to value, produces array

toJSONKeyText :: (a -> Text) -> ToJSONKeyFunction a Source #

Helper for creating textual keys.

instance ToJSONKey MyKey where
    toJSONKey = toJSONKeyText myKeyToText
      where
        myKeyToText = Text.pack . show -- or showt from text-show

contramapToJSONKeyFunction :: (b -> a) -> ToJSONKeyFunction a -> ToJSONKeyFunction b Source #

Contravariant map, as ToJSONKeyFunction is a contravariant functor.

class FromJSONKey a where Source #

Read the docs for ToJSONKey first. This class is a conversion in the opposite direction. If you have a newtype wrapper around Text, the recommended way to define instances is with generalized newtype deriving:

newtype SomeId = SomeId { getSomeId :: Text }
  deriving (Eq,Ord,Hashable,FromJSONKey)

Methods

fromJSONKey :: FromJSONKeyFunction a Source #

Strategy for parsing the key of a map-like container.

fromJSONKey :: FromJSON a => FromJSONKeyFunction a Source #

Strategy for parsing the key of a map-like container.

fromJSONKeyList :: FromJSONKeyFunction [a] Source #

This is similar in spirit to the readList method of Read. It makes it possible to give String keys special treatment without using OverlappingInstances. End users should always be able to use the default implementation of this method.

fromJSONKeyList :: FromJSON a => FromJSONKeyFunction [a] Source #

This is similar in spirit to the readList method of Read. It makes it possible to give String keys special treatment without using OverlappingInstances. End users should always be able to use the default implementation of this method.

Instances

FromJSONKey Bool Source # 
FromJSONKey Char Source # 
FromJSONKey Double Source # 
FromJSONKey Float Source # 
FromJSONKey Int Source # 
FromJSONKey Int8 Source # 
FromJSONKey Int16 Source # 
FromJSONKey Int32 Source # 
FromJSONKey Int64 Source # 
FromJSONKey Integer Source # 
FromJSONKey Natural Source # 
FromJSONKey Word Source # 
FromJSONKey Word8 Source # 
FromJSONKey Word16 Source # 
FromJSONKey Word32 Source # 
FromJSONKey Word64 Source # 
FromJSONKey Text Source # 
FromJSONKey Text Source # 
FromJSONKey Version Source # 
FromJSONKey ZonedTime Source # 
FromJSONKey LocalTime Source # 
FromJSONKey TimeOfDay Source # 
FromJSONKey UTCTime Source # 
FromJSONKey Day Source # 
FromJSONKey UUID Source # 
(FromJSONKey a, FromJSON a) => FromJSONKey [a] Source # 
FromJSONKey a => FromJSONKey (Identity a) Source # 
(FromJSON a, FromJSON b) => FromJSONKey (a, b) Source # 
(FromJSON a, FromJSON b, FromJSON c) => FromJSONKey (a, b, c) Source # 
FromJSONKey b => FromJSONKey (Tagged k a b) Source # 
(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSONKey (a, b, c, d) Source # 

data FromJSONKeyFunction a Source #

This type is related to ToJSONKeyFunction. If FromJSONKeyValue is used in the FromJSONKey instance, then ToJSONKeyValue should be used in the ToJSONKey instance. The other three data constructors for this type all correspond to ToJSONKeyText. Strictly speaking, FromJSONKeyTextParser is more powerful than FromJSONKeyText, which is in turn more powerful than FromJSONKeyCoerce. For performance reasons, these exist as three options instead of one.

Constructors

FromJSONKeyCoerce !(CoerceText a)

uses coerce (unsafeCoerce in older GHCs)

FromJSONKeyText !(Text -> a)

conversion from Text that always succeeds

FromJSONKeyTextParser !(Text -> Parser a)

conversion from Text that may fail

FromJSONKeyValue !(Value -> Parser a)

conversion for non-textual keys

Instances

Functor FromJSONKeyFunction Source #

Only law abiding up to interpretation

fromJSONKeyCoerce :: Coercible Text a => FromJSONKeyFunction a Source #

Construct FromJSONKeyFunction for types coercible from Text. This conversion is still unsafe, as Hashable and Eq instances of a should be compatible with Text i.e. hash values should be equal for wrapped values as well. This property will always be maintained if the Hashable and Eq instances are derived with generalized newtype deriving. compatible with Text i.e. hash values be equal for wrapped values as well.

On pre GHC 7.8 this is unconstrainted function.

coerceFromJSONKeyFunction :: Coercible a b => FromJSONKeyFunction a -> FromJSONKeyFunction b Source #

Semantically the same as coerceFromJSONKeyFunction = fmap coerce = coerce.

See note on fromJSONKeyCoerce.

mapFromJSONKeyFunction :: (a -> b) -> FromJSONKeyFunction a -> FromJSONKeyFunction b Source #

Same as fmap. Provided for the consistency with ToJSONKeyFunction.

Liftings to unary and binary type constructors

class FromJSON1 f where Source #

Lifting of the FromJSON class to unary type constructors.

Instead of manually writing your FromJSON1 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 liftParseJSON.

To use the second, simply add a deriving Generic1 clause to your datatype and declare a FromJSON1 instance for your datatype without giving a definition for liftParseJSON.

For example:

{-# LANGUAGE DeriveGeneric #-}

import GHC.Generics

data Pair a b = Pair { pairFst :: a, pairSnd :: b } deriving Generic1

instance FromJSON a => FromJSON1 (Pair a)

If the default implementation doesn't give exactly the results you want, you can customize the generic decoding with only a tiny amount of effort, using genericLiftParseJSON with your preferred Options:

customOptions = defaultOptions
                { fieldLabelModifier = map toUpper
                }

instance FromJSON a => FromJSON1 (Pair a) where
    liftParseJSON = genericLiftParseJSON customOptions

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (f a) Source #

liftParseJSON :: (Generic1 f, GFromJSON One (Rep1 f)) => (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (f a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [f a] Source #

Instances

FromJSON1 [] Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [a] Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [[a]] Source #

FromJSON1 Maybe Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Maybe a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Maybe a] Source #

FromJSON1 Min Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Min a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Min a] Source #

FromJSON1 Max Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Max a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Max a] Source #

FromJSON1 First Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (First a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [First a] Source #

FromJSON1 Last Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Last a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Last a] Source #

FromJSON1 WrappedMonoid Source # 
FromJSON1 Option Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Option a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Option a] Source #

FromJSON1 NonEmpty Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (NonEmpty a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [NonEmpty a] Source #

FromJSON1 Identity Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Identity a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Identity a] Source #

FromJSON1 Dual Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Dual a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Dual a] Source #

FromJSON1 First Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (First a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [First a] Source #

FromJSON1 Last Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Last a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Last a] Source #

FromJSON1 IntMap Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (IntMap a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [IntMap a] Source #

FromJSON1 Tree Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Tree a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Tree a] Source #

FromJSON1 Seq Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Seq a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Seq a] Source #

FromJSON1 DList Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (DList a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [DList a] Source #

FromJSON1 Vector Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Vector a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Vector a] Source #

FromJSON a => FromJSON1 (Either a) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Either a a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Either a a] Source #

FromJSON a => FromJSON1 ((,) a) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, a)] Source #

FromJSON1 (Proxy *) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Proxy * a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Proxy * a] Source #

(FromJSONKey k, Ord k) => FromJSON1 (Map k) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Map k a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Map k a] Source #

(FromJSONKey k, Eq k, Hashable k) => FromJSON1 (HashMap k) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (HashMap k a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [HashMap k a] Source #

(FromJSON a, FromJSON b) => FromJSON1 ((,,) a b) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, a)] Source #

FromJSON a => FromJSON1 (Const * a) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Const * a a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Const * a a] Source #

FromJSON1 (Tagged k a) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Tagged k a a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Tagged k a a] Source #

(FromJSON a, FromJSON b, FromJSON c) => FromJSON1 ((,,,) a b c) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, a)] Source #

(FromJSON1 f, FromJSON1 g) => FromJSON1 (Product * f g) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Product * f g a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Product * f g a] Source #

(FromJSON1 f, FromJSON1 g) => FromJSON1 (Sum * f g) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Sum * f g a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Sum * f g a] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON1 ((,,,,) a b c d) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, a)] Source #

(FromJSON1 f, FromJSON1 g) => FromJSON1 (Compose * * f g) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Compose * * f g a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Compose * * f g a] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON1 ((,,,,,) a b c d e) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON1 ((,,,,,,) a b c d e f) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON1 ((,,,,,,,) a b c d e f g) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h) => FromJSON1 ((,,,,,,,,) a b c d e f g h) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i) => FromJSON1 ((,,,,,,,,,) a b c d e f g h i) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j) => FromJSON1 ((,,,,,,,,,,) a b c d e f g h i j) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k) => FromJSON1 ((,,,,,,,,,,,) a b c d e f g h i j k) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, a)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l) => FromJSON1 ((,,,,,,,,,,,,) a b c d e f g h i j k l) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, a)] Source #

(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) => FromJSON1 ((,,,,,,,,,,,,,) a b c d e f g h i j k l m) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, a)] Source #

(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) => FromJSON1 ((,,,,,,,,,,,,,,) a b c d e f g h i j k l m n) Source # 

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, n, a) Source #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, a)] Source #

parseJSON1 :: (FromJSON1 f, FromJSON a) => Value -> Parser (f a) Source #

Lift the standard parseJSON function through the type constructor.

class FromJSON2 f where Source #

Lifting of the FromJSON class to binary type constructors.

Instead of manually writing your FromJSON2 instance, Data.Aeson.TH provides Template Haskell functions which will derive an instance at compile time.

Minimal complete definition

liftParseJSON2

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (f a b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [f a b] Source #

Instances

FromJSON2 Either Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (Either a b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [Either a b] Source #

FromJSON2 (,) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b)] Source #

FromJSON a => FromJSON2 ((,,) a) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, a, b)] Source #

FromJSON2 (Const *) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (Const * a b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [Const * a b] Source #

FromJSON2 (Tagged *) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (Tagged * a b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [Tagged * a b] Source #

(FromJSON a, FromJSON b) => FromJSON2 ((,,,) a b) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c) => FromJSON2 ((,,,,) a b c) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d) => FromJSON2 ((,,,,,) a b c d) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e) => FromJSON2 ((,,,,,,) a b c d e) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f) => FromJSON2 ((,,,,,,,) a b c d e f) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g) => FromJSON2 ((,,,,,,,,) a b c d e f g) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h) => FromJSON2 ((,,,,,,,,,) a b c d e f g h) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i) => FromJSON2 ((,,,,,,,,,,) a b c d e f g h i) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j) => FromJSON2 ((,,,,,,,,,,,) a b c d e f g h i j) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k) => FromJSON2 ((,,,,,,,,,,,,) a b c d e f g h i j k) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, a, b)] Source #

(FromJSON a, FromJSON b, FromJSON c, FromJSON d, FromJSON e, FromJSON f, FromJSON g, FromJSON h, FromJSON i, FromJSON j, FromJSON k, FromJSON l) => FromJSON2 ((,,,,,,,,,,,,,) a b c d e f g h i j k l) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, a, b)] Source #

(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) => FromJSON2 ((,,,,,,,,,,,,,,) a b c d e f g h i j k l m) Source # 

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (a, b, c, d, e, f, g, h, i, j, k, l, m, a, b) Source #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [(a, b, c, d, e, f, g, h, i, j, k, l, m, a, b)] Source #

parseJSON2 :: (FromJSON2 f, FromJSON a, FromJSON b) => Value -> Parser (f a b) Source #

Lift the standard parseJSON function through the type constructor.

class ToJSON1 f where Source #

Lifting of the ToJSON class to unary type constructors.

Instead of manually writing your ToJSON1 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 toJSON1.

To use the second, simply add a deriving Generic1 clause to your datatype and declare a ToJSON1 instance for your datatype without giving definitions for liftToJSON or liftToEncoding.

For example:

{-# LANGUAGE DeriveGeneric #-}

import GHC.Generics

data Pair = Pair { pairFst :: a, pairSnd :: b } deriving Generic1

instance ToJSON a => ToJSON1 (Pair a)

If the default implementation doesn't give exactly the results you want, you can customize the generic encoding with only a tiny amount of effort, using genericLiftToJSON and genericLiftToEncoding with your preferred Options:

customOptions = defaultOptions
                { fieldLabelModifier = map toUpper
                }

instance ToJSON a => ToJSON1 (Pair a) where
    liftToJSON     = genericLiftToJSON customOptions
    liftToEncoding = genericLiftToEncoding customOptions

See also ToJSON.

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> f a -> Value Source #

liftToJSON :: (Generic1 f, GToJSON Value One (Rep1 f)) => (a -> Value) -> ([a] -> Value) -> f a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [f a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> f a -> Encoding Source #

liftToEncoding :: (Generic1 f, GToJSON Encoding One (Rep1 f)) => (a -> Encoding) -> ([a] -> Encoding) -> f a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [f a] -> Encoding Source #

Instances

ToJSON1 [] Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> [a] -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [[a]] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> [a] -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [[a]] -> Encoding Source #

ToJSON1 Maybe Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Maybe a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Maybe a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Maybe a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Maybe a] -> Encoding Source #

ToJSON1 Min Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Min a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Min a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Min a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Min a] -> Encoding Source #

ToJSON1 Max Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Max a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Max a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Max a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Max a] -> Encoding Source #

ToJSON1 First Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> First a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [First a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> First a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [First a] -> Encoding Source #

ToJSON1 Last Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Last a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Last a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Last a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Last a] -> Encoding Source #

ToJSON1 WrappedMonoid Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> WrappedMonoid a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [WrappedMonoid a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> WrappedMonoid a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [WrappedMonoid a] -> Encoding Source #

ToJSON1 Option Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Option a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Option a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Option a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Option a] -> Encoding Source #

ToJSON1 NonEmpty Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> NonEmpty a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [NonEmpty a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> NonEmpty a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [NonEmpty a] -> Encoding Source #

ToJSON1 Identity Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Identity a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Identity a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Identity a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Identity a] -> Encoding Source #

ToJSON1 Dual Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Dual a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Dual a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Dual a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Dual a] -> Encoding Source #

ToJSON1 First Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> First a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [First a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> First a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [First a] -> Encoding Source #

ToJSON1 Last Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Last a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Last a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Last a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Last a] -> Encoding Source #

ToJSON1 IntMap Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> IntMap a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [IntMap a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> IntMap a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [IntMap a] -> Encoding Source #

ToJSON1 Tree Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Tree a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Tree a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Tree a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Tree a] -> Encoding Source #

ToJSON1 Seq Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Seq a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Seq a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Seq a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Seq a] -> Encoding Source #

ToJSON1 Set Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Set a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Set a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Set a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Set a] -> Encoding Source #

ToJSON1 DList Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> DList a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [DList a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> DList a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [DList a] -> Encoding Source #

ToJSON1 HashSet Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> HashSet a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [HashSet a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> HashSet a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [HashSet a] -> Encoding Source #

ToJSON1 Vector Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Vector a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Vector a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Vector a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Vector a] -> Encoding Source #

ToJSON a => ToJSON1 (Either a) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Either a a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Either a a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Either a a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Either a a] -> Encoding Source #

ToJSON a => ToJSON1 ((,) a) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, a)] -> Encoding Source #

ToJSON1 (Proxy *) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Proxy * a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Proxy * a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Proxy * a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Proxy * a] -> Encoding Source #

ToJSONKey k => ToJSON1 (Map k) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Map k a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Map k a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Map k a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Map k a] -> Encoding Source #

ToJSONKey k => ToJSON1 (HashMap k) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> HashMap k a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [HashMap k a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> HashMap k a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [HashMap k a] -> Encoding Source #

(ToJSON a, ToJSON b) => ToJSON1 ((,,) a b) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, a)] -> Encoding Source #

ToJSON a => ToJSON1 (Const * a) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Const * a a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Const * a a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Const * a a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Const * a a] -> Encoding Source #

ToJSON1 (Tagged k a) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Tagged k a a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Tagged k a a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Tagged k a a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Tagged k a a] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c) => ToJSON1 ((,,,) a b c) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, a)] -> Encoding Source #

(ToJSON1 f, ToJSON1 g) => ToJSON1 (Product * f g) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Product * f g a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Product * f g a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Product * f g a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Product * f g a] -> Encoding Source #

(ToJSON1 f, ToJSON1 g) => ToJSON1 (Sum * f g) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Sum * f g a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Sum * f g a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Sum * f g a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Sum * f g a] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON1 ((,,,,) a b c d) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, a)] -> Encoding Source #

(ToJSON1 f, ToJSON1 g) => ToJSON1 (Compose * * f g) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Compose * * f g a -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Compose * * f g a] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Compose * * f g a -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Compose * * f g a] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON1 ((,,,,,) a b c d e) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON1 ((,,,,,,) a b c d e f) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON1 ((,,,,,,,) a b c d e f g) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h) => ToJSON1 ((,,,,,,,,) a b c d e f g h) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i) => ToJSON1 ((,,,,,,,,,) a b c d e f g h i) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j) => ToJSON1 ((,,,,,,,,,,) a b c d e f g h i j) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, j, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k) => ToJSON1 ((,,,,,,,,,,,) a b c d e f g h i j k) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, a)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l) => ToJSON1 ((,,,,,,,,,,,,) a b c d e f g h i j k l) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, l, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, l, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a)] -> Encoding Source #

(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) => ToJSON1 ((,,,,,,,,,,,,,) a b c d e f g h i j k l m) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a)] -> Encoding Source #

(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) => ToJSON1 ((,,,,,,,,,,,,,,) a b c d e f g h i j k l m n) Source # 

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, a) -> Value Source #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, a)] -> Value Source #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, a) -> Encoding Source #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, a)] -> Encoding Source #

toJSON1 :: (ToJSON1 f, ToJSON a) => f a -> Value Source #

Lift the standard toJSON function through the type constructor.

toEncoding1 :: (ToJSON1 f, ToJSON a) => f a -> Encoding Source #

Lift the standard toEncoding function through the type constructor.

class ToJSON2 f where Source #

Lifting of the ToJSON class to binary type constructors.

Instead of manually writing your ToJSON2 instance, Data.Aeson.TH provides Template Haskell functions which will derive an instance at compile time.

The compiler cannot provide a default generic implementation for liftToJSON2, unlike toJSON and liftToJSON.

Minimal complete definition

liftToJSON2, liftToEncoding2

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> f a b -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [f a b] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> f a b -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [f a b] -> Encoding Source #

Instances

ToJSON2 Either Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> Either a b -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [Either a b] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> Either a b -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [Either a b] -> Encoding Source #

ToJSON2 (,) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b)] -> Encoding Source #

ToJSON a => ToJSON2 ((,,) a) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, a, b)] -> Encoding Source #

ToJSON2 (Const *) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> Const * a b -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [Const * a b] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> Const * a b -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [Const * a b] -> Encoding Source #

ToJSON2 (Tagged *) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> Tagged * a b -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [Tagged * a b] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> Tagged * a b -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [Tagged * a b] -> Encoding Source #

(ToJSON a, ToJSON b) => ToJSON2 ((,,,) a b) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c) => ToJSON2 ((,,,,) a b c) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON2 ((,,,,,) a b c d) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON2 ((,,,,,,) a b c d e) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON2 ((,,,,,,,) a b c d e f) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON2 ((,,,,,,,,) a b c d e f g) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h) => ToJSON2 ((,,,,,,,,,) a b c d e f g h) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i) => ToJSON2 ((,,,,,,,,,,) a b c d e f g h i) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, i, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, i, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, i, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j) => ToJSON2 ((,,,,,,,,,,,) a b c d e f g h i j) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, i, j, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k) => ToJSON2 ((,,,,,,,,,,,,) a b c d e f g h i j k) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, a, b)] -> Encoding Source #

(ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g, ToJSON h, ToJSON i, ToJSON j, ToJSON k, ToJSON l) => ToJSON2 ((,,,,,,,,,,,,,) a b c d e f g h i j k l) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, l, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, l, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a, b)] -> Encoding Source #

(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) => ToJSON2 ((,,,,,,,,,,,,,,) a b c d e f g h i j k l m) Source # 

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a, b) -> Value Source #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a, b)] -> Value Source #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a, b) -> Encoding Source #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a, b)] -> Encoding Source #

toJSON2 :: (ToJSON2 f, ToJSON a, ToJSON b) => f a b -> Value Source #

Lift the standard toJSON function through the type constructor.

toEncoding2 :: (ToJSON2 f, ToJSON a, ToJSON b) => f a b -> Encoding Source #

Lift the standard toEncoding function through the type constructor.

Generic JSON classes

class GFromJSON arity f where Source #

Class of generic representation types that can be converted from JSON.

Minimal complete definition

gParseJSON

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (f a) Source #

This method (applied to defaultOptions) is used as the default generic implementation of parseJSON (if the arity is Zero) or liftParseJSON (if the arity is One).

Instances

GFromJSON One Par1 Source # 
GFromJSON arity (U1 *) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (U1 * a) Source #

FromJSON1 f => GFromJSON One (Rec1 * f) Source # 

Methods

gParseJSON :: Options -> FromArgs One a -> Value -> Parser (Rec1 * f a) Source #

(AllNullary ((:+:) * a b) allNullary, ParseSum * arity ((:+:) * a b) allNullary) => GFromJSON arity ((:+:) * a b) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser ((* :+: a) b a) Source #

(FromProduct arity a, FromProduct arity b, ProductSize a, ProductSize b) => GFromJSON arity ((:*:) * a b) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser ((* :*: a) b a) Source #

ConsFromJSON arity a => GFromJSON arity (C1 * c a) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (C1 * c a a) Source #

(ConsFromJSON arity a, AllNullary (C1 * c a) allNullary, ParseSum * arity (C1 * c a) allNullary) => GFromJSON arity (D1 * d (C1 * c a)) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (D1 * d (C1 * c a) a) Source #

FromJSON a => GFromJSON arity (K1 * i a) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (K1 * i a a) Source #

GFromJSON arity a => GFromJSON arity (M1 * i c a) Source # 

Methods

gParseJSON :: Options -> FromArgs arity a -> Value -> Parser (M1 * i c a a) Source #

(FromJSON1 f, GFromJSON One g) => GFromJSON One ((:.:) * * f g) Source # 

Methods

gParseJSON :: Options -> FromArgs One a -> Value -> Parser ((* :.: *) f g a) Source #

data FromArgs arity a where Source #

A FromArgs value either stores nothing (for FromJSON) or it stores the two function arguments that decode occurrences of the type parameter (for FromJSON1).

Constructors

NoFromArgs :: FromArgs Zero a 
From1Args :: (Value -> Parser a) -> (Value -> Parser [a]) -> FromArgs One a 

type GToJSON = GToJSON Value Source #

type GToEncoding = GToJSON Encoding Source #

data ToArgs res arity a where Source #

A ToArgs value either stores nothing (for ToJSON) or it stores the two function arguments that encode occurrences of the type parameter (for ToJSON1).

Constructors

NoToArgs :: ToArgs res Zero a 
To1Args :: (a -> res) -> ([a] -> res) -> ToArgs res One a 

data Zero Source #

A type-level indicator that ToJSON or FromJSON is being derived generically.

data One Source #

A type-level indicator that ToJSON1 or FromJSON1 is being derived generically.

Instances

genericToJSON :: (Generic a, GToJSON Value Zero (Rep a)) => Options -> a -> Value Source #

A configurable generic JSON creator. This function applied to defaultOptions is used as the default for toJSON when the type is an instance of Generic.

genericLiftToJSON :: (Generic1 f, GToJSON Value One (Rep1 f)) => Options -> (a -> Value) -> ([a] -> Value) -> f a -> Value Source #

A configurable generic JSON creator. This function applied to defaultOptions is used as the default for liftToJSON when the type is an instance of Generic1.

genericToEncoding :: (Generic a, GToJSON Encoding Zero (Rep a)) => Options -> a -> Encoding Source #

A configurable generic JSON encoder. This function applied to defaultOptions is used as the default for toEncoding when the type is an instance of Generic.

genericLiftToEncoding :: (Generic1 f, GToJSON Encoding One (Rep1 f)) => Options -> (a -> Encoding) -> ([a] -> Encoding) -> f a -> Encoding Source #

A configurable generic JSON encoder. This function applied to defaultOptions is used as the default for liftToEncoding when the type is an instance of Generic1.

genericParseJSON :: (Generic a, GFromJSON Zero (Rep a)) => Options -> Value -> Parser a Source #

A configurable generic JSON decoder. This function applied to defaultOptions is used as the default for parseJSON when the type is an instance of Generic.

genericLiftParseJSON :: (Generic1 f, GFromJSON One (Rep1 f)) => Options -> (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (f a) Source #

A configurable generic JSON decoder. This function applied to defaultOptions is used as the default for liftParseJSON when the type is an instance of Generic1.

Inspecting Values

withObject :: String -> (Object -> Parser a) -> Value -> Parser a Source #

withObject expected f value applies f to the Object when value is an Object and fails using typeMismatch expected otherwise.

withText :: String -> (Text -> Parser a) -> Value -> Parser a Source #

withText expected f value applies f to the Text when value is a String and fails using typeMismatch expected otherwise.

withArray :: String -> (Array -> Parser a) -> Value -> Parser a Source #

withArray expected f value applies f to the Array when value is an Array and fails using typeMismatch expected otherwise.

withScientific :: String -> (Scientific -> Parser a) -> Value -> Parser a Source #

withScientific expected f value applies f to the Scientific number when value is a Number and fails using typeMismatch expected otherwise. . Warning: If you are converting from a scientific to an unbounded type such as Integer you may want to add a restriction on the size of the exponent (see withBoundedScientific) to prevent malicious input from filling up the memory of the target system.

withBool :: String -> (Bool -> Parser a) -> Value -> Parser a Source #

withBool expected f value applies f to the Bool when value is a Bool and fails using typeMismatch expected otherwise.

withEmbeddedJSON :: String -> (Value -> Parser a) -> Value -> Parser a Source #

Decode a nested JSON-encoded string.

pairs :: Series -> Encoding Source #

Encode a series of key/value pairs, separated by commas.

foldable :: (Foldable t, ToJSON a) => t a -> Encoding Source #

Encode a Foldable as a JSON array.

(.:) :: FromJSON a => Object -> Text -> Parser a Source #

Retrieve the value associated with the given key of an Object. The result is empty if the key is not present or the value cannot be converted to the desired type.

This accessor is appropriate if the key and value must be present in an object for it to be valid. If the key and value are optional, use .:? instead.

(.:?) :: FromJSON a => Object -> Text -> Parser (Maybe a) Source #

Retrieve the value associated with the given key of an Object. The result is Nothing if the key is not present or if its value is Null, or empty if the value cannot be converted to the desired type.

This accessor is most useful if the key and value can be absent from an object without affecting its validity. If the key and value are mandatory, use .: instead.

(.:!) :: FromJSON a => Object -> Text -> Parser (Maybe a) Source #

Retrieve the value associated with the given key of an Object. The result is Nothing if the key is not present or empty if the value cannot be converted to the desired type.

This differs from .:? by attempting to parse Null the same as any other JSON value, instead of interpreting it as Nothing.

(.!=) :: Parser (Maybe a) -> a -> Parser a Source #

Helper for use in combination with .:? to provide default values for optional JSON object fields.

This combinator is most useful if the key and value can be absent from an object without affecting its validity and we know a default value to assign in that case. If the key and value are mandatory, use .: instead.

Example usage:

 v1 <- o .:? "opt_field_with_dfl" .!= "default_val"
 v2 <- o .:  "mandatory_field"
 v3 <- o .:? "opt_field2"

object :: [Pair] -> Value Source #

Create a Value from a list of name/value Pairs. If duplicate keys arise, earlier keys and their associated values win.

parseField :: FromJSON a => Object -> Text -> Parser a Source #

Function variant of .:.

parseFieldMaybe :: FromJSON a => Object -> Text -> Parser (Maybe a) Source #

Function variant of .:?.

parseFieldMaybe' :: FromJSON a => Object -> Text -> Parser (Maybe a) Source #

Function variant of .:!.

explicitParseField :: (Value -> Parser a) -> Object -> Text -> Parser a Source #

Variant of .: with explicit parser function.

E.g. explicitParseField parseJSON1 :: (FromJSON1 f, FromJSON a) -> Object -> Text -> Parser (f a)

explicitParseFieldMaybe :: (Value -> Parser a) -> Object -> Text -> Parser (Maybe a) Source #

Variant of .:? with explicit parser function.

explicitParseFieldMaybe' :: (Value -> Parser a) -> Object -> Text -> Parser (Maybe a) Source #

Variant of .:! with explicit parser function.

listEncoding :: (a -> Encoding) -> [a] -> Encoding Source #

Helper function to use with liftToEncoding. Useful when writing own ToJSON1 instances.

newtype F a = F [a]

-- This instance encodes String as an array of chars
instance ToJSON1 F where
    liftToJSON     tj _ (F xs) = liftToJSON     tj (listValue    tj) xs
    liftToEncoding te _ (F xs) = liftToEncoding te (listEncoding te) xs

instance FromJSON1 F where
    liftParseJSON p _ v = F <$> liftParseJSON p (listParser p) v

listValue :: (a -> Value) -> [a] -> Value Source #

Helper function to use with liftToJSON, see listEncoding.

listParser :: (Value -> Parser a) -> Value -> Parser [a] Source #

Helper function to use with liftParseJSON. See listEncoding.

Generic and TH encoding configuration

data Options Source #

Options that specify how to encode/decode your datatype to/from JSON.

Options can be set using record syntax on defaultOptions with the fields below.

Instances

Options fields

The functions here are in fact record fields of the Options type.

fieldLabelModifier :: Options -> String -> String Source #

Function applied to field labels. Handy for removing common record prefixes for example.

constructorTagModifier :: Options -> String -> String Source #

Function applied to constructor tags which could be handy for lower-casing them for example.

allNullaryToStringTag :: Options -> Bool Source #

If True the constructors of a datatype, with all nullary constructors, will be encoded to just a string with the constructor tag. If False the encoding will always follow the sumEncoding.

omitNothingFields :: Options -> Bool Source #

If True record fields with a Nothing value will be omitted from the resulting object. If False the resulting object will include those fields mapping to null.

sumEncoding :: Options -> SumEncoding Source #

Specifies how to encode constructors of a sum datatype.

unwrapUnaryRecords :: Options -> Bool Source #

Hide the field name when a record constructor has only one field, like a newtype.

tagSingleConstructors :: Options -> Bool Source #

Encode types with a single constructor as sums, so that allNullaryToStringTag and sumEncoding apply.

Options utilities

data SumEncoding Source #

Specifies how to encode constructors of a sum datatype.

Constructors

TaggedObject

A constructor will be encoded to an object with a field tagFieldName which specifies the constructor tag (modified by the constructorTagModifier). If the constructor is a record the encoded record fields will be unpacked into this object. So make sure that your record doesn't have a field with the same label as the tagFieldName. Otherwise the tag gets overwritten by the encoded value of that field! If the constructor is not a record the encoded constructor contents will be stored under the contentsFieldName field.

UntaggedValue

Constructor names won't be encoded. Instead only the contents of the constructor will be encoded as if the type had a single constructor. JSON encodings have to be disjoint for decoding to work properly.

When decoding, constructors are tried in the order of definition. If some encodings overlap, the first one defined will succeed.

Note: Nullary constructors are encoded as strings (using constructorTagModifier). Having a nullary constructor alongside a single field constructor that encodes to a string leads to ambiguity.

Note: Only the last error is kept when decoding, so in the case of malformed JSON, only an error for the last constructor will be reported.

ObjectWithSingleField

A constructor will be encoded to an object with a single field named after the constructor tag (modified by the constructorTagModifier) which maps to the encoded contents of the constructor.

TwoElemArray

A constructor will be encoded to a 2-element array where the first element is the tag of the constructor (modified by the constructorTagModifier) and the second element the encoded contents of the constructor.

camelTo :: Char -> String -> String Source #

Deprecated: Use camelTo2 for better results

Converts from CamelCase to another lower case, interspersing the character between all capital letters and their previous entries, except those capital letters that appear together, like API.

For use by Aeson template haskell calls.

camelTo '_' 'CamelCaseAPI' == "camel_case_api"

camelTo2 :: Char -> String -> String Source #

Better version of camelTo. Example where it works better:

camelTo '_' 'CamelAPICase' == "camel_apicase"
camelTo2 '_' 'CamelAPICase' == "camel_api_case"

defaultTaggedObject :: SumEncoding Source #

Default TaggedObject SumEncoding options:

defaultTaggedObject = TaggedObject
                      { tagFieldName      = "tag"
                      , contentsFieldName = "contents"
                      }