| Copyright |
(c) 2011-2016 Bryan O'Sullivan
(c) 2011 MailRank Inc. |
|---|---|
| License | BSD3 |
| Maintainer | Bryan O'Sullivan <bos@serpentine.com> |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | None |
| Language | Haskell2010 |
Data.Aeson.Types
Description
Types for working with JSON data.
Synopsis
- data Value
- data Key
- type Encoding = Encoding' Value
- unsafeToEncoding :: Builder -> Encoding' a
- fromEncoding :: Encoding' tag -> Builder
- data Series
- type Array = Vector Value
- emptyArray :: Value
- type Pair = ( Key , Value )
- type Object = KeyMap Value
- emptyObject :: Value
- newtype DotNetTime = DotNetTime { }
- typeMismatch :: String -> Value -> Parser a
- unexpected :: Value -> Parser a
- data Parser a
- data Result a
- class FromJSON a where
- fromJSON :: FromJSON a => Value -> Result a
- parse :: (a -> Parser b) -> a -> Result b
- parseEither :: (a -> Parser b) -> a -> Either String b
- parseMaybe :: (a -> Parser b) -> a -> Maybe b
- parseFail :: String -> Parser a
-
class
ToJSON
a
where
- toJSON :: a -> Value
- toEncoding :: a -> Encoding
- toJSONList :: [a] -> Value
- toEncodingList :: [a] -> Encoding
- class KeyValue kv where
- modifyFailure :: ( String -> String ) -> Parser a -> Parser a
- prependFailure :: String -> Parser a -> Parser a
- parserThrowError :: JSONPath -> String -> Parser a
- parserCatchError :: Parser a -> ( JSONPath -> String -> Parser a) -> Parser a
-
class
ToJSONKey
a
where
- toJSONKey :: ToJSONKeyFunction a
- toJSONKeyList :: ToJSONKeyFunction [a]
-
data
ToJSONKeyFunction
a
- = ToJSONKeyText !(a -> Key ) !(a -> Encoding' Key )
- | ToJSONKeyValue !(a -> Value ) !(a -> Encoding )
- toJSONKeyText :: (a -> Text ) -> ToJSONKeyFunction a
- toJSONKeyKey :: (a -> Key ) -> ToJSONKeyFunction a
- contramapToJSONKeyFunction :: (b -> a) -> ToJSONKeyFunction a -> ToJSONKeyFunction b
- class FromJSONKey a where
-
data
FromJSONKeyFunction
a
where
- FromJSONKeyCoerce :: Coercible Text a => FromJSONKeyFunction a
- FromJSONKeyText :: !( Text -> a) -> FromJSONKeyFunction a
- FromJSONKeyTextParser :: !( Text -> Parser a) -> FromJSONKeyFunction a
- FromJSONKeyValue :: !( Value -> Parser a) -> FromJSONKeyFunction a
- fromJSONKeyCoerce :: Coercible Text a => FromJSONKeyFunction a
- coerceFromJSONKeyFunction :: Coercible a b => FromJSONKeyFunction a -> FromJSONKeyFunction b
- mapFromJSONKeyFunction :: (a -> b) -> FromJSONKeyFunction a -> FromJSONKeyFunction b
- class GetConName f => GToJSONKey f
- genericToJSONKey :: ( Generic a, GToJSONKey ( Rep a)) => JSONKeyOptions -> ToJSONKeyFunction a
- class (ConstructorNames f, SumFromString f) => GFromJSONKey f
- genericFromJSONKey :: forall a. ( Generic a, GFromJSONKey ( Rep a)) => JSONKeyOptions -> FromJSONKeyFunction a
- class FromJSON1 f where
- parseJSON1 :: ( FromJSON1 f, FromJSON a) => Value -> Parser (f a)
- class FromJSON2 f where
- parseJSON2 :: ( FromJSON2 f, FromJSON a, FromJSON b) => Value -> Parser (f a b)
-
class
ToJSON1
f
where
- liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> f a -> Value
- liftToJSONList :: (a -> Value ) -> ([a] -> Value ) -> [f a] -> Value
- liftToEncoding :: (a -> Encoding ) -> ([a] -> Encoding ) -> f a -> Encoding
- liftToEncodingList :: (a -> Encoding ) -> ([a] -> Encoding ) -> [f a] -> Encoding
- toJSON1 :: ( ToJSON1 f, ToJSON a) => f a -> Value
- toEncoding1 :: ( ToJSON1 f, ToJSON a) => f a -> Encoding
-
class
ToJSON2
f
where
- liftToJSON2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> f a b -> Value
- liftToJSONList2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> [f a b] -> Value
- liftToEncoding2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> f a b -> Encoding
- liftToEncodingList2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> [f a b] -> Encoding
- toJSON2 :: ( ToJSON2 f, ToJSON a, ToJSON b) => f a b -> Value
- toEncoding2 :: ( ToJSON2 f, ToJSON a, ToJSON b) => f a b -> Encoding
- class GFromJSON arity f
- data FromArgs arity a
- type GToJSON = GToJSON' Value
- type GToEncoding = GToJSON' Encoding
- class GToJSON' enc arity f
- data ToArgs res arity a
- data Zero
- data One
- genericToJSON :: ( Generic a, GToJSON' Value Zero ( Rep a)) => Options -> a -> Value
- genericLiftToJSON :: ( Generic1 f, GToJSON' Value One ( Rep1 f)) => Options -> (a -> Value ) -> ([a] -> Value ) -> f a -> Value
- genericToEncoding :: ( Generic a, GToJSON' Encoding Zero ( Rep a)) => Options -> a -> Encoding
- genericLiftToEncoding :: ( Generic1 f, GToJSON' Encoding One ( Rep1 f)) => Options -> (a -> Encoding ) -> ([a] -> Encoding ) -> f a -> Encoding
- genericParseJSON :: ( Generic a, GFromJSON Zero ( Rep a)) => Options -> Value -> Parser a
- genericLiftParseJSON :: ( Generic1 f, GFromJSON One ( Rep1 f)) => Options -> ( Value -> Parser a) -> ( Value -> Parser [a]) -> Value -> Parser (f a)
- withObject :: String -> ( Object -> Parser a) -> Value -> Parser a
- withText :: String -> ( Text -> Parser a) -> Value -> Parser a
- withArray :: String -> ( Array -> Parser a) -> Value -> Parser a
- withScientific :: String -> ( Scientific -> Parser a) -> Value -> Parser a
- withBool :: String -> ( Bool -> Parser a) -> Value -> Parser a
- withEmbeddedJSON :: String -> ( Value -> Parser a) -> Value -> Parser a
- pairs :: Series -> Encoding
- foldable :: ( Foldable t, ToJSON a) => t a -> Encoding
- (.:) :: FromJSON a => Object -> Key -> Parser a
- (.:?) :: FromJSON a => Object -> Key -> Parser ( Maybe a)
- (.:!) :: FromJSON a => Object -> Key -> Parser ( Maybe a)
- (.!=) :: Parser ( Maybe a) -> a -> Parser a
- object :: [ Pair ] -> Value
- parseField :: FromJSON a => Object -> Key -> Parser a
- parseFieldMaybe :: FromJSON a => Object -> Key -> Parser ( Maybe a)
- parseFieldMaybe' :: FromJSON a => Object -> Key -> Parser ( Maybe a)
- explicitParseField :: ( Value -> Parser a) -> Object -> Key -> Parser a
- explicitParseFieldMaybe :: ( Value -> Parser a) -> Object -> Key -> Parser ( Maybe a)
- explicitParseFieldMaybe' :: ( Value -> Parser a) -> Object -> Key -> Parser ( Maybe a)
- listEncoding :: (a -> Encoding ) -> [a] -> Encoding
- listValue :: (a -> Value ) -> [a] -> Value
- listParser :: ( Value -> Parser a) -> Value -> Parser [a]
- data Options
- fieldLabelModifier :: Options -> String -> String
- constructorTagModifier :: Options -> String -> String
- allNullaryToStringTag :: Options -> Bool
- omitNothingFields :: Options -> Bool
- sumEncoding :: Options -> SumEncoding
- unwrapUnaryRecords :: Options -> Bool
- tagSingleConstructors :: Options -> Bool
- rejectUnknownFields :: Options -> Bool
-
data
SumEncoding
- = TaggedObject { }
- | UntaggedValue
- | ObjectWithSingleField
- | TwoElemArray
- camelTo :: Char -> String -> String
- camelTo2 :: Char -> String -> String
- defaultOptions :: Options
- defaultTaggedObject :: SumEncoding
- data JSONKeyOptions
- keyModifier :: JSONKeyOptions -> String -> String
- defaultJSONKeyOptions :: JSONKeyOptions
- (<?>) :: Parser a -> JSONPathElement -> Parser a
- type JSONPath = [ JSONPathElement ]
- data JSONPathElement
- formatPath :: JSONPath -> String
- formatRelativePath :: JSONPath -> String
Core JSON types
A JSON value represented as a Haskell value.
Instances
| Eq Value Source # | |
| Data Value Source # | |
|
Defined in Data.Aeson.Types.Internal Methods gfoldl :: ( forall d b. Data d => c (d -> b) -> d -> c b) -> ( forall g. g -> c g) -> Value -> c Value Source # gunfold :: ( forall b r. Data b => c (b -> r) -> c r) -> ( forall r. r -> c r) -> Constr -> c Value Source # toConstr :: Value -> Constr Source # dataTypeOf :: Value -> DataType Source # dataCast1 :: Typeable t => ( forall d. Data d => c (t d)) -> Maybe (c Value ) Source # dataCast2 :: Typeable t => ( forall d e. ( Data d, Data e) => c (t d e)) -> Maybe (c Value ) Source # gmapT :: ( forall b. Data b => b -> b) -> Value -> Value Source # gmapQl :: (r -> r' -> r) -> r -> ( forall d. Data d => d -> r') -> Value -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> ( forall d. Data d => d -> r') -> Value -> r Source # gmapQ :: ( forall d. Data d => d -> u) -> Value -> [u] Source # gmapQi :: Int -> ( forall d. Data d => d -> u) -> Value -> u Source # gmapM :: Monad m => ( forall d. Data d => d -> m d) -> Value -> m Value Source # gmapMp :: MonadPlus m => ( forall d. Data d => d -> m d) -> Value -> m Value Source # gmapMo :: MonadPlus m => ( forall d. Data d => d -> m d) -> Value -> m Value Source # |
|
| Ord Value Source # |
The ordering is total, consistent with
Since: 1.5.2.0 |
|
Defined in Data.Aeson.Types.Internal |
|
| Read Value Source # | |
| Show Value Source # |
Since version 1.5.6.0 version object values are printed in lexicographic key order
|
| IsString Value Source # | |
|
Defined in Data.Aeson.Types.Internal Methods fromString :: String -> Value Source # |
|
| Generic Value Source # | |
| NFData Value Source # | |
|
Defined in Data.Aeson.Types.Internal |
|
| Hashable Value Source # | |
| FromJSON Value Source # | |
| KeyValue Pair Source # | |
| KeyValue Object Source # |
Constructs a singleton
|
| ToJSON Value Source # | |
| Lift Value Source # |
Since: 0.11.0.0 |
| GToJSON' Value arity ( U1 :: Type -> Type ) Source # | |
| GToJSON' Value arity ( V1 :: Type -> Type ) Source # | |
| GToJSON' Encoding arity ( U1 :: Type -> Type ) Source # | |
| ToJSON1 f => GToJSON' Value One ( Rec1 f) Source # | |
| ToJSON1 f => GToJSON' Encoding One ( Rec1 f) Source # | |
| (WriteProduct arity a, WriteProduct arity b, ProductSize a, ProductSize b) => GToJSON' Value arity (a :*: b) Source # | |
| ToJSON a => GToJSON' Value arity ( K1 i a :: Type -> Type ) Source # | |
| (EncodeProduct arity a, EncodeProduct arity b) => GToJSON' Encoding arity (a :*: b) Source # | |
| ToJSON a => GToJSON' Encoding arity ( K1 i a :: Type -> Type ) Source # | |
| ( ToJSON1 f, GToJSON' Value One g) => GToJSON' Value One (f :.: g) Source # | |
| ( ToJSON1 f, GToJSON' Encoding One g) => GToJSON' Encoding One (f :.: g) Source # | |
| type Rep Value Source # | |
|
Defined in Data.Aeson.Types.Internal
type
Rep
Value
=
D1
('
MetaData
"Value" "Data.Aeson.Types.Internal" "aeson-2.0.2.0-Hbc7lMoCN3S5f36Jsk6Tpd" '
False
) ((
C1
('
MetaCons
"Object" '
PrefixI
'
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
SourceStrict
'
DecidedStrict
) (
Rec0
Object
))
:+:
(
C1
('
MetaCons
"Array" '
PrefixI
'
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
SourceStrict
'
DecidedStrict
) (
Rec0
Array
))
:+:
C1
('
MetaCons
"String" '
PrefixI
'
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
SourceStrict
'
DecidedStrict
) (
Rec0
Text
))))
:+:
(
C1
('
MetaCons
"Number" '
PrefixI
'
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
SourceStrict
'
DecidedStrict
) (
Rec0
Scientific
))
:+:
(
C1
('
MetaCons
"Bool" '
PrefixI
'
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
SourceStrict
'
DecidedStrict
) (
Rec0
Bool
))
:+:
C1
('
MetaCons
"Null" '
PrefixI
'
False
) (
U1
::
Type
->
Type
))))
|
|
Instances
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.
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)
emptyArray :: Value Source #
The empty array.
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
|
|
Instances
Arguments
| :: String |
The name of the JSON type being parsed
(
|
| -> Value |
The actual value encountered. |
| -> Parser a |
Fail parsing due to a type mismatch, with a descriptive message.
The following wrappers should generally be prefered:
withObject
,
withArray
,
withText
,
withBool
.
Error message example
typeMismatch "Object" (String "oops") -- Error: "expected Object, but encountered String"
unexpected :: Value -> Parser a Source #
Fail parsing due to a type mismatch, when the expected types are implicit.
Error message example
unexpected (String "oops") -- Error: "unexpected String"
Type conversion
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.
The result of running a
Parser
.
Instances
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:
-
failyields a custom error message: it is the recommended way of reporting a failure; -
empty(ormzero) is uninformative: use it when the error is meant to be caught by some(;<|>) -
typeMismatchcan be used to report a failure when the encountered value is not of the expected JSON type;unexpectedis an appropriate alternative when more than one type may be expected, or to keep the expected type implicit.
prependFailure
(or
modifyFailure
) add more information to a parser's
error messages.
An example type and instance using
typeMismatch
and
prependFailure
:
-- Allow ourselves to writeTextliterals. {-# LANGUAGE OverloadedStrings #-} data Coord = Coord { x :: Double, y :: Double } instanceFromJSONCoord whereparseJSON(Objectv) = Coord<$>v.:"x"<*>v.:"y" -- We do not expect a non-Objectvalue here. -- We could useemptyto fail, buttypeMismatch-- gives a much more informative error message.parseJSONinvalid =prependFailure"parsing Coord failed, " (typeMismatch"Object" invalid)
For this common case of only being concerned with a single
type of JSON value, the functions
withObject
,
withScientific
, 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:
instanceFromJSONCoord whereparseJSON=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
clause to your
datatype and declare a
Generic
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 =
; if you need different
options, you can customize the generic decoding by defining:
genericParseJSON
defaultOptions
customOptions =defaultOptions{fieldLabelModifier=maptoUpper} instanceFromJSONCoord whereparseJSON=genericParseJSONcustomOptions
Minimal complete definition
Nothing
Instances
fromJSON :: FromJSON a => Value -> Result a Source #
Convert a value from JSON, failing if the types do not match.
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 writeTextliterals. {-# LANGUAGE OverloadedStrings #-} data Coord = Coord { x :: Double, y :: Double } instanceToJSONCoord wheretoJSON(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
clause to your
datatype and declare a
Generic
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=maptoUpper} instanceToJSONCoord wheretoJSON=genericToJSONcustomOptionstoEncoding=genericToEncodingcustomOptions
Previous versions of this library only had the
toJSON
method. Adding
toEncoding
had two reasons:
-
toEncoding is more efficient for the common case that the output of
toJSONis directly serialized to aByteString. Further, expressing either method in terms of the other would be non-optimal. -
The choice of defaults allows a smooth transition for existing users:
Existing instances that do not define
toEncodingstill compile and have the correct semantics. This is ensured by making the default implementation oftoEncodingusetoJSON. This produces correct results, but since it performs an intermediate conversion to aValue, it will be less efficient than directly emitting anEncoding. (this also means that specifying nothing more thaninstance ToJSON Coordwould be sufficient as a generically decoding instance, but there probably exists no good reason to not specifytoEncodingin new instances.)
Minimal complete definition
Nothing
Methods
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.
instanceToJSONCoord wheretoEncoding=genericToEncodingdefaultOptions
toJSONList :: [a] -> Value Source #
toEncodingList :: [a] -> Encoding Source #
Instances
class KeyValue kv where Source #
A key-value pair for encoding a JSON object.
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
prependFailure :: String -> Parser a -> Parser a Source #
If the inner
Parser
failed, prepend the given string to the failure
message.
prependFailures =modifyFailure(s++)
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
ToJSONKeyText
can be used instead of
ToJSONKeyValue
to encode maps
as objects instead of arrays of pairs. This instance may be
implemented using generics as follows:
instanceToJSONKeyColor wheretoJSONKey=genericToJSONKeydefaultJSONKeyOptions
Low-level implementations
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.
Minimal complete definition
Nothing
Methods
toJSONKey :: ToJSONKeyFunction a Source #
Strategy for rendering the key for a map-like container.
default toJSONKey :: ToJSON a => ToJSONKeyFunction a Source #
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.
default toJSONKeyList :: ToJSON a => ToJSONKeyFunction [a] Source #
Instances
data ToJSONKeyFunction a Source #
Constructors
| ToJSONKeyText !(a -> Key ) !(a -> Encoding' Key ) |
key is encoded to string, produces object |
| ToJSONKeyValue !(a -> Value ) !(a -> Encoding ) |
key is encoded to value, produces array |
Instances
| Contravariant ToJSONKeyFunction Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods contramap :: (a -> b) -> ToJSONKeyFunction b -> ToJSONKeyFunction a Source # (>$) :: b -> ToJSONKeyFunction b -> ToJSONKeyFunction a Source # |
|
toJSONKeyText :: (a -> Text ) -> ToJSONKeyFunction a Source #
Helper for creating textual keys.
instanceToJSONKeyMyKey wheretoJSONKey=toJSONKeyTextmyKeyToText where myKeyToText = Text.pack . show -- or showt from text-show
toJSONKeyKey :: (a -> Key ) -> ToJSONKeyFunction a Source #
Since: 2.0.0.0
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)
If you have a sum of nullary constructors, you may use the generic implementation:
data Color = Red | Green | Blue deriving Generic instanceFromJSONKeyColor wherefromJSONKey=genericFromJSONKeydefaultJSONKeyOptions
Minimal complete definition
Nothing
Methods
fromJSONKey :: FromJSONKeyFunction a Source #
Strategy for parsing the key of a map-like container.
default fromJSONKey :: FromJSON a => FromJSONKeyFunction a Source #
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.
default fromJSONKeyList :: FromJSON a => FromJSONKeyFunction [a] Source #
Instances
data FromJSONKeyFunction a where 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 | |
| FromJSONKeyText | |
|
Fields
|
|
| FromJSONKeyTextParser | |
|
Fields
|
|
| FromJSONKeyValue | |
|
Fields
|
|
Instances
| Functor FromJSONKeyFunction Source # |
Only law abiding up to interpretation |
|
Defined in Data.Aeson.Types.FromJSON Methods fmap :: (a -> b) -> FromJSONKeyFunction a -> FromJSONKeyFunction b Source # (<$) :: a -> FromJSONKeyFunction b -> FromJSONKeyFunction a Source # |
|
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
.
Generic keys
class GetConName f => GToJSONKey f Source #
Instances
| GetConName f => GToJSONKey (f :: k -> Type ) Source # | |
|
Defined in Data.Aeson.Types.ToJSON |
|
genericToJSONKey :: ( Generic a, GToJSONKey ( Rep a)) => JSONKeyOptions -> ToJSONKeyFunction a Source #
class (ConstructorNames f, SumFromString f) => GFromJSONKey f Source #
Instances
| (ConstructorNames f, SumFromString f) => GFromJSONKey f Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
genericFromJSONKey :: forall a. ( Generic a, GFromJSONKey ( Rep a)) => JSONKeyOptions -> FromJSONKeyFunction a Source #
fromJSONKey
for
Generic
types.
These types must be sums of nullary constructors, whose names will be used
as keys for JSON objects.
See also
genericToJSONKey
.
Example
data Color = Red | Green | Blue derivingGenericinstanceFromJSONKeyColor wherefromJSONKey=genericFromJSONKeydefaultJSONKeyOptions
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
clause to your
datatype and declare a
Generic1
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=maptoUpper} instanceFromJSONa =>FromJSON1(Pair a) whereliftParseJSON=genericLiftParseJSONcustomOptions
Minimal complete definition
Nothing
Methods
liftParseJSON :: ( Value -> Parser a) -> ( Value -> Parser [a]) -> Value -> Parser (f a) Source #
default 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
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
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
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
clause to your
datatype and declare a
Generic1
ToJSON1
instance for your datatype without giving
definitions for
liftToJSON
or
liftToEncoding
.
For example:
{-# LANGUAGE DeriveGeneric #-}
import GHC.Generics
data Pair a b = 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=maptoUpper} instanceToJSONa =>ToJSON1(Pair a) whereliftToJSON=genericLiftToJSONcustomOptionsliftToEncoding=genericLiftToEncodingcustomOptions
See also
ToJSON
.
Minimal complete definition
Nothing
Methods
liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> f a -> Value Source #
default 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 #
default 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 Solo Source # |
Since: 2.0.2.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> Solo a -> Value Source # liftToJSONList :: (a -> Value ) -> ([a] -> Value ) -> [ Solo a] -> Value Source # liftToEncoding :: (a -> Encoding ) -> ([a] -> Encoding ) -> Solo a -> Encoding Source # liftToEncodingList :: (a -> Encoding ) -> ([a] -> Encoding ) -> [ Solo a] -> Encoding Source # |
|
| ToJSON1 Min Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 Identity Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 First Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 Dual Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 NonEmpty Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 IntMap Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 DNonEmpty Source # |
Since: 1.5.3.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> DNonEmpty a -> Value Source # liftToJSONList :: (a -> Value ) -> ([a] -> Value ) -> [ DNonEmpty a] -> Value Source # liftToEncoding :: (a -> Encoding ) -> ([a] -> Encoding ) -> DNonEmpty a -> Encoding Source # liftToEncodingList :: (a -> Encoding ) -> ([a] -> Encoding ) -> [ DNonEmpty a] -> Encoding Source # |
|
| ToJSON1 DList Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 Maybe Source # |
Since: 1.5.3.0 |
|
Defined in Data.Aeson.Types.ToJSON 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 HashSet Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # |
|
| ToJSON1 KeyMap Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> KeyMap a -> Value Source # liftToJSONList :: (a -> Value ) -> ([a] -> Value ) -> [ KeyMap a] -> Value Source # liftToEncoding :: (a -> Encoding ) -> ([a] -> Encoding ) -> KeyMap a -> Encoding Source # liftToEncodingList :: (a -> Encoding ) -> ([a] -> Encoding ) -> [ KeyMap a] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( Either a) Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> Either a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ Either a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> Either a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ Either a a0] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( (,) a) Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, a0)] -> Encoding Source # |
|
| ToJSON1 ( Proxy :: Type -> Type ) Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # |
|
| ToJSON a => ToJSON1 ( These a) Source # |
Since: 1.5.1.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> These a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ These a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> These a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ These a a0] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( Pair a) Source # |
Since: 1.5.3.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> Pair a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ Pair a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> Pair a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ Pair a a0] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( These a) Source # |
Since: 1.5.3.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> These a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ These a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> These a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ These a a0] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( Either a) Source # |
Since: 1.5.3.0 |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> Either a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ Either a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> Either a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ Either a a0] -> Encoding Source # |
|
| ToJSONKey k => ToJSON1 ( HashMap k) Source # | |
|
Defined in Data.Aeson.Types.ToJSON 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 # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, a0)] -> Encoding Source # |
|
| ToJSON a => ToJSON1 ( Const a :: Type -> Type ) Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> Const a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ Const a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> Const a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ Const a a0] -> Encoding Source # |
|
| ToJSON1 ( Tagged a) Source # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> Tagged a a0 -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [ Tagged a a0] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> Tagged a a0 -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [ Tagged a a0] -> Encoding Source # |
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| ( ToJSON1 f, ToJSON1 g) => ToJSON1 ( These1 f g) Source # |
Since: 1.5.1.0 |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a -> Value ) -> ([a] -> Value ) -> These1 f g a -> Value Source # liftToJSONList :: (a -> Value ) -> ([a] -> Value ) -> [ These1 f g a] -> Value Source # liftToEncoding :: (a -> Encoding ) -> ([a] -> Encoding ) -> These1 f g a -> Encoding Source # liftToEncodingList :: (a -> Encoding ) -> ([a] -> Encoding ) -> [ These1 f g a] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c) => ToJSON1 ( (,,,) a b c) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, a0)] -> Encoding Source # |
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| ( ToJSON1 f, ToJSON1 g) => ToJSON1 ( Product f g) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ( ToJSON1 f, ToJSON1 g) => ToJSON1 ( Sum f g) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON1 ( (,,,,) a b c d) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, a0)] -> Encoding Source # |
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| ( ToJSON1 f, ToJSON1 g) => ToJSON1 ( Compose f g) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON1 ( (,,,,,) a b c d e) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, a0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON1 ( (,,,,,,) a b c d e f) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, a0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON1 ( (,,,,,,,) a b c d e f g) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, l, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, l, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON :: (a0 -> Value ) -> ([a0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, a0) -> Value Source # liftToJSONList :: (a0 -> Value ) -> ([a0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, a0)] -> Value Source # liftToEncoding :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, a0) -> Encoding Source # liftToEncodingList :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, a0)] -> Encoding Source # |
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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
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 # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ToJSON2 (,) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ToJSON2 These Source # |
Since: 1.5.1.0 |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> These a b -> Value Source # liftToJSONList2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> [ These a b] -> Value Source # liftToEncoding2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> These a b -> Encoding Source # liftToEncodingList2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> [ These a b] -> Encoding Source # |
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| ToJSON2 Pair Source # |
Since: 1.5.3.0 |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> Pair a b -> Value Source # liftToJSONList2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> [ Pair a b] -> Value Source # liftToEncoding2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> Pair a b -> Encoding Source # liftToEncodingList2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> [ Pair a b] -> Encoding Source # |
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| ToJSON2 These Source # |
Since: 1.5.3.0 |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> These a b -> Value Source # liftToJSONList2 :: (a -> Value ) -> ([a] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> [ These a b] -> Value Source # liftToEncoding2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> These a b -> Encoding Source # liftToEncodingList2 :: (a -> Encoding ) -> ([a] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> [ These a b] -> Encoding Source # |
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| ToJSON2 Either Source # |
Since: 1.5.3.0 |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ToJSON a => ToJSON2 ( (,,) a) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> (a, a0, b) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b -> Value ) -> ([b] -> Value ) -> [(a, a0, b)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> (a, a0, b) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b -> Encoding ) -> ([b] -> Encoding ) -> [(a, a0, b)] -> Encoding Source # |
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| ToJSON2 ( Const :: Type -> Type -> Type ) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ToJSON2 ( Tagged :: Type -> Type -> Type ) Source # | |
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Defined in Data.Aeson.Types.ToJSON 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 # |
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| ( ToJSON a, ToJSON b) => ToJSON2 ( (,,,) a b) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, a0, b0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c) => ToJSON2 ( (,,,,) a b c) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, a0, b0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d) => ToJSON2 ( (,,,,,) a b c d) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, a0, b0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e) => ToJSON2 ( (,,,,,,) a b c d e) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, a0, b0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f) => ToJSON2 ( (,,,,,,,) a b c d e f) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, a0, b0)] -> Encoding Source # |
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| ( ToJSON a, ToJSON b, ToJSON c, ToJSON d, ToJSON e, ToJSON f, ToJSON g) => ToJSON2 ( (,,,,,,,,) a b c d e f g) Source # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, a0, b0)] -> Encoding Source # |
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| ( 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 # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, a0, b0)] -> Encoding Source # |
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| ( 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 # | |
|
Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, i, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, a0, b0)] -> 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, a0, b0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, a0, b0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, l, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, l, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, a0, b0)] -> Encoding Source # |
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| ( 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 # | |
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Defined in Data.Aeson.Types.ToJSON Methods liftToJSON2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a0, b0) -> Value Source # liftToJSONList2 :: (a0 -> Value ) -> ([a0] -> Value ) -> (b0 -> Value ) -> ([b0] -> Value ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a0, b0)] -> Value Source # liftToEncoding2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, a0, b0) -> Encoding Source # liftToEncodingList2 :: (a0 -> Encoding ) -> ([a0] -> Encoding ) -> (b0 -> Encoding ) -> ([b0] -> Encoding ) -> [(a, b, c, d, e, f, g, h, i, j, k, l, m, a0, b0)] -> 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 Source #
Class of generic representation types that can be converted from JSON.
Minimal complete definition
gParseJSON
Instances
| GFromJSON One Par1 Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| GFromJSON arity ( V1 :: Type -> Type ) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| FromJSON1 f => GFromJSON One ( Rec1 f) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| (GFromJSON' arity a, Datatype d) => GFromJSON arity ( D1 d a) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| FromJSON a => GFromJSON arity ( K1 i a :: Type -> Type ) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| GFromJSON arity a => GFromJSON arity ( M1 i c a) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| ( FromJSON1 f, GFromJSON One g) => GFromJSON One (f :.: g) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
type GToEncoding = GToJSON' Encoding Source #
class GToJSON' enc arity f Source #
Class of generic representation types that can be converted to JSON.
Minimal complete definition
gToJSON
Instances
| GToJSON' enc One Par1 Source # | |
| GToJSON' Value arity ( U1 :: Type -> Type ) Source # | |
| GToJSON' Value arity ( V1 :: Type -> Type ) Source # | |
| GToJSON' Encoding arity ( U1 :: Type -> Type ) Source # | |
| ToJSON1 f => GToJSON' Value One ( Rec1 f) Source # | |
| ToJSON1 f => GToJSON' Encoding One ( Rec1 f) Source # | |
| (AllNullary (a :+: b) allNullary, SumToJSON enc arity (a :+: b) allNullary) => GToJSON' enc arity (a :+: b) Source # | |
|
Defined in Data.Aeson.Types.ToJSON |
|
| ConsToJSON enc arity a => GToJSON' enc arity ( C1 c a) Source # | |
|
Defined in Data.Aeson.Types.ToJSON |
|
| (ConsToJSON enc arity a, AllNullary ( C1 c a) allNullary, SumToJSON enc arity ( C1 c a) allNullary) => GToJSON' enc arity ( D1 d ( C1 c a)) Source # | |
| (WriteProduct arity a, WriteProduct arity b, ProductSize a, ProductSize b) => GToJSON' Value arity (a :*: b) Source # | |
| ToJSON a => GToJSON' Value arity ( K1 i a :: Type -> Type ) Source # | |
| (EncodeProduct arity a, EncodeProduct arity b) => GToJSON' Encoding arity (a :*: b) Source # | |
| ToJSON a => GToJSON' Encoding arity ( K1 i a :: Type -> Type ) Source # | |
| GToJSON' enc arity a => GToJSON' enc arity ( M1 i c a) Source # | |
|
Defined in Data.Aeson.Types.ToJSON |
|
| ( ToJSON1 f, GToJSON' Value One g) => GToJSON' Value One (f :.: g) Source # | |
| ( ToJSON1 f, GToJSON' Encoding One g) => GToJSON' Encoding One (f :.: g) Source # | |
A type-level indicator that
ToJSON1
or
FromJSON1
is being derived generically.
Instances
| GFromJSON One Par1 Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| GToJSON' enc One Par1 Source # | |
| ToJSON1 f => GToJSON' Value One ( Rec1 f) Source # | |
| ToJSON1 f => GToJSON' Encoding One ( Rec1 f) Source # | |
| ( ToJSON1 f, GToJSON' Value One g) => GToJSON' Value One (f :.: g) Source # | |
| ( ToJSON1 f, GToJSON' Encoding One g) => GToJSON' Encoding One (f :.: g) Source # | |
| FromJSON1 f => GFromJSON One ( Rec1 f) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
| ( FromJSON1 f, GFromJSON One g) => GFromJSON One (f :.: g) Source # | |
|
Defined in Data.Aeson.Types.FromJSON |
|
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
Value
s
Value
s
withObject :: String -> ( Object -> Parser a) -> Value -> Parser a Source #
applies
withObject
name f value
f
to the
Object
when
value
is an
Object
and fails otherwise.
Error message example
withObject "MyType" f (String "oops") -- Error: "parsing MyType failed, expected Object, but encountered String"
withScientific :: String -> ( Scientific -> Parser a) -> Value -> Parser a Source #
applies
withScientific
name f value
f
to the
Scientific
number
when
value
is a
Number
and fails using
typeMismatch
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.
Error message example
withScientific "MyType" f (String "oops") -- Error: "parsing MyType failed, expected Number, but encountered String"
withEmbeddedJSON :: String -> ( Value -> Parser a) -> Value -> Parser a Source #
Decode a nested JSON-encoded string.
(.:) :: FromJSON a => Object -> Key -> 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 -> Key -> 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.
(.!=) :: 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"
parseFieldMaybe :: FromJSON a => Object -> Key -> Parser ( Maybe a) Source #
Function variant of
.:?
.
parseFieldMaybe' :: FromJSON a => Object -> Key -> Parser ( Maybe a) Source #
Function variant of
.:!
.
explicitParseField :: ( Value -> Parser a) -> Object -> Key -> 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 -> Key -> Parser ( Maybe a) Source #
Variant of
.:?
with explicit parser function.
explicitParseFieldMaybe' :: ( Value -> Parser a) -> Object -> Key -> 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 encodesStringas an array of chars instanceToJSON1F whereliftToJSONtj _ (F xs) =liftToJSONtj (listValuetj) xsliftToEncodingte _ (F xs) =liftToEncodingte (listEncodingte) xs instanceFromJSON1F whereliftParseJSONp _ v = F <$>liftParseJSONp (listParserp) 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
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.
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
.
Note that this
does not
affect parsing:
Maybe
fields are
optional regardless of the value of
omitNothingFields
, subject
to the note below.
Note
Setting
omitNothingFields
to
True
only affects fields which are of
type
Maybe
uniformly
in the
ToJSON
instance.
In particular, if the type of a field is declared as a type variable, it
will not be omitted from the JSON object, unless the field is
specialized upfront in the instance.
The same holds for
Maybe
fields being optional in the
FromJSON
instance.
Example
The generic instance for the following type
Fruit
depends on whether
the instance head is
Fruit a
or
Fruit (Maybe a)
.
data Fruit a = Fruit
{ apples :: a -- A field whose type is a type variable.
, oranges :: Maybe Int
} deriving Generic
-- apples required, oranges optional
-- Even if fromJSON is then specialized to (Fruit (Maybe a)).
instance FromJSON a => FromJSON (Fruit a)
-- apples optional, oranges optional
-- In this instance, the field apples is uniformly of type (Maybe a).
instance FromJSON a => FromJSON (Fruit (Maybe a))
options :: Options
options = defaultOptions { omitNothingFields = True }
-- apples always present in the output, oranges is omitted if Nothing
instance ToJSON a => ToJSON (Fruit a) where
toJSON = genericToJSON options
-- both apples and oranges are omitted if Nothing
instance ToJSON a => ToJSON (Fruit (Maybe a)) where
toJSON = genericToJSON options
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.
rejectUnknownFields :: Options -> Bool Source #
Applies only to
FromJSON
instances. If a field appears in
the parsed object map, but does not appear in the target object, parsing
will fail, with an error message indicating which fields were unknown.
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
|
|
Fields |
|
| 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
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
|
| TwoElemArray |
A constructor will be encoded to a 2-element array where the
first element is the tag of the constructor (modified by the
|
Instances
| Eq SumEncoding Source # | |
|
Defined in Data.Aeson.Types.Internal Methods (==) :: SumEncoding -> SumEncoding -> Bool Source # (/=) :: SumEncoding -> SumEncoding -> Bool Source # |
|
| Show SumEncoding Source # | |
|
Defined in Data.Aeson.Types.Internal |
|
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"
defaultOptions :: Options Source #
Default encoding
Options
:
Options{fieldLabelModifier= id ,constructorTagModifier= id ,allNullaryToStringTag= True ,omitNothingFields= False ,sumEncoding=defaultTaggedObject,unwrapUnaryRecords= False ,tagSingleConstructors= False ,rejectUnknownFields= False }
defaultTaggedObject :: SumEncoding Source #
Default
TaggedObject
SumEncoding
options:
defaultTaggedObject =TaggedObject{tagFieldName= "tag" ,contentsFieldName= "contents" }
Options for object keys
data JSONKeyOptions Source #
Options for encoding keys with
genericFromJSONKey
and
genericToJSONKey
.
keyModifier :: JSONKeyOptions -> String -> String Source #
Function applied to keys. Its result is what goes into the encoded
Value
.
Example
The following instances encode the constructor
Bar
to lower-case keys
"bar"
.
data Foo = Bar derivingGenericopts ::JSONKeyOptionsopts =defaultJSONKeyOptions{keyModifier=toLower} instanceToJSONKeyFoo wheretoJSONKey=genericToJSONKeyopts instanceFromJSONKeyFoo wherefromJSONKey=genericFromJSONKeyopts
defaultJSONKeyOptions :: JSONKeyOptions Source #
Default
JSONKeyOptions
:
defaultJSONKeyOptions =JSONKeyOptions{keyModifier=id}
Parsing context
(<?>) :: Parser a -> JSONPathElement -> Parser a Source #
Add JSON Path context to a parser
When parsing a complex structure, it helps to annotate (sub)parsers with context, so that if an error occurs, you can find its location.
withObject "Person" $ \o ->
Person
<$> o .: "name" <?> Key "name"
<*> o .: "age" <?> Key "age"
(Standard methods like
(.:)
already do this.)
With such annotations, if an error occurs, you will get a JSON Path location of that error.
Since 0.10
type JSONPath = [ JSONPathElement ] Source #
data JSONPathElement Source #
Elements of a JSON path used to describe the location of an error.
Constructors
| Key Key |
JSON path element of a key into an object, "object.key". |
| Index ! Int |
JSON path element of an index into an array, "array[index]". |
Instances
| Eq JSONPathElement Source # | |
|
Defined in Data.Aeson.Types.Internal Methods (==) :: JSONPathElement -> JSONPathElement -> Bool Source # (/=) :: JSONPathElement -> JSONPathElement -> Bool Source # |
|
| Ord JSONPathElement Source # | |
|
Defined in Data.Aeson.Types.Internal Methods compare :: JSONPathElement -> JSONPathElement -> Ordering Source # (<) :: JSONPathElement -> JSONPathElement -> Bool Source # (<=) :: JSONPathElement -> JSONPathElement -> Bool Source # (>) :: JSONPathElement -> JSONPathElement -> Bool Source # (>=) :: JSONPathElement -> JSONPathElement -> Bool Source # max :: JSONPathElement -> JSONPathElement -> JSONPathElement Source # min :: JSONPathElement -> JSONPathElement -> JSONPathElement Source # |
|
| Show JSONPathElement Source # | |
|
Defined in Data.Aeson.Types.Internal |
|
| NFData JSONPathElement Source # | |
|
Defined in Data.Aeson.Types.Internal Methods rnf :: JSONPathElement -> () Source # |
|
formatPath :: JSONPath -> String Source #