Aeson.ValueParser

A parser DSL for the "aeson" model of the JSON tree.

Documentation

data Value a

A JSON Value parser.

Instances

Monad Value

Defined in Aeson.ValueParser

Methods

(>>=) :: Value a -> (a -> Value b) -> Value b

(>>) :: Value a -> Value b -> Value b

return :: a -> Value a

fail :: String -> Value a

Functor Value

Defined in Aeson.ValueParser

Methods

fmap :: (a -> b) -> Value a -> Value b

(<$) :: a -> Value b -> Value a

MonadFail Value

Defined in Aeson.ValueParser

Methods

fail :: String -> Value a

Applicative Value

Defined in Aeson.ValueParser

Methods

pure :: a -> Value a

(<*>) :: Value (a -> b) -> Value a -> Value b

liftA2 :: (a -> b -> c) -> Value a -> Value b -> Value c

(*>) :: Value a -> Value b -> Value b

(<*) :: Value a -> Value b -> Value a

Alternative Value

Defined in Aeson.ValueParser

Methods

empty :: Value a

(<|>) :: Value a -> Value a -> Value a

some :: Value a -> Value [a]

many :: Value a -> Value [a]

MonadPlus Value

Defined in Aeson.ValueParser

Methods

mzero :: Value a

mplus :: Value a -> Value a -> Value a

MonadError Error Value

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Value a

catchError :: Value a -> (Error -> Value a) -> Value a

run :: Value a -> Value -> Either Error a

data Error

Constructors

Error

Fields

• [Text]

  Path

• Text

  Message

Instances

IsString Error

Defined in Aeson.ValueParser.Error

Methods

fromString :: String -> Error

Semigroup Error

Defined in Aeson.ValueParser.Error

Methods

(<>) :: Error -> Error -> Error

sconcat :: NonEmpty Error -> Error

stimes :: Integral b => b -> Error -> Error

Monoid Error

Defined in Aeson.ValueParser.Error

Methods

mempty :: Error

mappend :: Error -> Error -> Error

mconcat :: [Error] -> Error

MonadError Error Array

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Array a

catchError :: Array a -> (Error -> Array a) -> Array a

MonadError Error Object

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Object a

catchError :: Object a -> (Error -> Object a) -> Object a

MonadError Error Value

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Value a

catchError :: Value a -> (Error -> Value a) -> Value a

Value parsers

object :: Object a -> Value a

array :: Array a -> Value a

null :: Value ()

nullable :: Value a -> Value (Maybe a)

string :: Value Text

stringAsBytes :: Value ByteString

number :: Value Scientific

numberAsInt :: Value Int

bool :: Value Bool

fromJSON :: FromJSON a => Value a

Object parsers

data Object a

A JSON Value parser.

Instances

Monad Object

Defined in Aeson.ValueParser

Methods

(>>=) :: Object a -> (a -> Object b) -> Object b

(>>) :: Object a -> Object b -> Object b

return :: a -> Object a

fail :: String -> Object a

Functor Object

Defined in Aeson.ValueParser

Methods

fmap :: (a -> b) -> Object a -> Object b

(<$) :: a -> Object b -> Object a

MonadFail Object

Defined in Aeson.ValueParser

Methods

fail :: String -> Object a

Applicative Object

Defined in Aeson.ValueParser

Methods

pure :: a -> Object a

(<*>) :: Object (a -> b) -> Object a -> Object b

liftA2 :: (a -> b -> c) -> Object a -> Object b -> Object c

(*>) :: Object a -> Object b -> Object b

(<*) :: Object a -> Object b -> Object a

Alternative Object

Defined in Aeson.ValueParser

Methods

empty :: Object a

(<|>) :: Object a -> Object a -> Object a

some :: Object a -> Object [a]

many :: Object a -> Object [a]

MonadPlus Object

Defined in Aeson.ValueParser

Methods

mzero :: Object a

mplus :: Object a -> Object a -> Object a

MonadError Error Object

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Object a

catchError :: Object a -> (Error -> Object a) -> Object a

field :: Text -> Value a -> Object a

oneOfFields :: [Text] -> Value a -> Object a

fieldOr

Arguments

:: Text

Field name

-> Value a

Field parser

-> Object a

Alternative branch

-> Object a

Applies the value parser to the existing field, propagating its errors accordingly. Only if the field does not exist, it executes Alternative branch. IOW, it won't execute Alternative branch if Field parser fails. This is what distinguishes fieldOr name parser from the seemingly same mplus (field name parser)

oneOfFieldsOr :: [Text] -> Value a -> Object a -> Object a

Same as fieldOr, with the only difference that it enumerates the provided list of field names parsing the first existing one.

possibleField :: Text -> Value a -> Object (Maybe a)

Applies the value parser to the existing field, propagating its errors accordingly, but unlike field it doesn't fail if the field does not exist. The Maybe wrapper is there to cover such a case.

oneOfPossibleFields :: [Text] -> Value a -> Object (Maybe a)

Same as possibleField, with the only difference that it enumerates the provided list of field names parsing the first existing one.

fieldMap :: Value a -> Object (HashMap Text a)

foldlFields :: (state -> Text -> field -> state) -> state -> Value field -> Object state

Array parsers

data Array a

A JSON Value parser.

Instances

Monad Array

Defined in Aeson.ValueParser

Methods

(>>=) :: Array a -> (a -> Array b) -> Array b

(>>) :: Array a -> Array b -> Array b

return :: a -> Array a

fail :: String -> Array a

Functor Array

Defined in Aeson.ValueParser

Methods

fmap :: (a -> b) -> Array a -> Array b

(<$) :: a -> Array b -> Array a

MonadFail Array

Defined in Aeson.ValueParser

Methods

fail :: String -> Array a

Applicative Array

Defined in Aeson.ValueParser

Methods

pure :: a -> Array a

(<*>) :: Array (a -> b) -> Array a -> Array b

liftA2 :: (a -> b -> c) -> Array a -> Array b -> Array c

(*>) :: Array a -> Array b -> Array b

(<*) :: Array a -> Array b -> Array a

Alternative Array

Defined in Aeson.ValueParser

Methods

empty :: Array a

(<|>) :: Array a -> Array a -> Array a

some :: Array a -> Array [a]

many :: Array a -> Array [a]

MonadPlus Array

Defined in Aeson.ValueParser

Methods

mzero :: Array a

mplus :: Array a -> Array a -> Array a

MonadError Error Array

Defined in Aeson.ValueParser

Methods

throwError :: Error -> Array a

catchError :: Array a -> (Error -> Array a) -> Array a

element :: Int -> Value a -> Array a

elementOr :: Int -> Value a -> Array a -> Array a

possibleElement :: Int -> Value a -> Array (Maybe a)

elementVector :: Value a -> Array (Vector a)

foldlElements :: (state -> Int -> element -> state) -> state -> Value element -> Array state

foldrElements :: (Int -> element -> state -> state) -> state -> Value element -> Array state