Copyright	(C) 2015 Oleg Grenrus
License	BSD3
Maintainer	Oleg Grenrus <oleg.grenrus@iki.fi>
Safe Haskell	None
Language	Haskell2010

Data.Aeson.Extra

Contents

Generic maps
Symbol tag
Singleton object
CollapsedList
Re-exports

Description

More or less useful newtypes for writing FromJSON & ToJSON instances

Synopsis

Generic maps

newtype M a Source

A wrapper type to parse arbitrary maps

λ > decode "{\"1\": 1, \"2\": 2}" :: Maybe (M (H.HashMap Int Int))
Just (M {getMap = fromList [(1,1),(2,2)]})

Constructors

M
Fields getMap :: a

Instances

Functor M Source
Methods fmap :: (a -> b) -> M a -> M b (<$) :: a -> M b -> M a
Foldable M Source
Methods fold :: Monoid m => M m -> m foldMap :: Monoid m => (a -> m) -> M a -> m foldr :: (a -> b -> b) -> b -> M a -> b foldr' :: (a -> b -> b) -> b -> M a -> b foldl :: (b -> a -> b) -> b -> M a -> b foldl' :: (b -> a -> b) -> b -> M a -> b foldr1 :: (a -> a -> a) -> M a -> a foldl1 :: (a -> a -> a) -> M a -> a toList :: M a -> [a] null :: M a -> Bool length :: M a -> Int elem :: Eq a => a -> M a -> Bool maximum :: Ord a => M a -> a minimum :: Ord a => M a -> a sum :: Num a => M a -> a product :: Num a => M a -> a
Traversable M Source
Methods traverse :: Applicative f => (a -> f b) -> M a -> f (M b) sequenceA :: Applicative f => M (f a) -> f (M a) mapM :: Monad m => (a -> m b) -> M a -> m (M b) sequence :: Monad m => M (m a) -> m (M a)
Eq a => Eq (M a) Source
Methods (==) :: M a -> M a -> Bool (/=) :: M a -> M a -> Bool
Ord a => Ord (M a) Source
Methods compare :: M a -> M a -> Ordering (<) :: M a -> M a -> Bool (<=) :: M a -> M a -> Bool (>) :: M a -> M a -> Bool (>=) :: M a -> M a -> Bool max :: M a -> M a -> M a min :: M a -> M a -> M a
Read a => Read (M a) Source
Methods readsPrec :: Int -> ReadS (M a) readList :: ReadS [M a] readPrec :: ReadPrec (M a) readListPrec :: ReadPrec [M a]
Show a => Show (M a) Source
Methods showsPrec :: Int -> M a -> ShowS show :: M a -> String showList :: [M a] -> ShowS
ToJSONMap m k v => ToJSON (M m) Source
Methods toJSON :: M m -> Value
FromJSONMap m k v => FromJSON (M m) Source
Methods parseJSON :: Value -> Parser (M m)

class FromJSONKey a where Source

Methods

parseJSONKey :: Text -> Parser a Source

Instances

FromJSONKey Int Source
Methods parseJSONKey :: Text -> Parser Int Source
FromJSONKey Integer Source
Methods parseJSONKey :: Text -> Parser Integer Source
FromJSONKey String Source
Methods parseJSONKey :: Text -> Parser String Source
FromJSONKey Text Source
Methods parseJSONKey :: Text -> Parser Text Source
FromJSONKey Text Source
Methods parseJSONKey :: Text -> Parser Text Source

parseIntegralJSONKey :: Integral a => Text -> Parser a Source

class FromJSONMap m k v | m -> k v where Source

Methods

parseJSONMap :: HashMap Text Value -> Parser m Source

Instances

(Eq k, Hashable k, FromJSONKey k, FromJSON v) => FromJSONMap (HashMap k v) k v Source
Methods parseJSONMap :: HashMap Text Value -> Parser (HashMap k v) Source
(Ord k, FromJSONKey k, FromJSON v) => FromJSONMap (Map k v) k v Source
Methods parseJSONMap :: HashMap Text Value -> Parser (Map k v) Source

class ToJSONKey a where Source

Methods

toJSONKey :: a -> Text Source

Instances

ToJSONKey Int Source
Methods toJSONKey :: Int -> Text Source
ToJSONKey Integer Source
Methods toJSONKey :: Integer -> Text Source
ToJSONKey String Source
Methods toJSONKey :: String -> Text Source
ToJSONKey Text Source
Methods toJSONKey :: Text -> Text Source
ToJSONKey Text Source
Methods toJSONKey :: Text -> Text Source

class ToJSONMap m k v | m -> k v where Source

Methods

toJSONMap :: m -> HashMap Text Value Source

Instances

(ToJSONKey k, ToJSON v) => ToJSONMap (HashMap k v) k v Source
Methods toJSONMap :: HashMap k v -> HashMap Text Value Source
(ToJSONKey k, ToJSON v) => ToJSONMap (Map k v) k v Source
Methods toJSONMap :: Map k v -> HashMap Text Value Source

Symbol tag

data SymTag s Source

Singleton string encoded and decoded as ifself.

λ> encode (Sym :: Sym "foobar")
"\"foobar\""

decode "\"foobar\"" :: Maybe (Sym "foobar")
Just Sym

decode "\"foobar\"" :: Maybe (Sym "barfoo")
Nothing

Constructors

SymTag

Instances

Bounded (SymTag s) Source
Methods minBound :: SymTag s maxBound :: SymTag s
Enum (SymTag s) Source
Methods succ :: SymTag s -> SymTag s pred :: SymTag s -> SymTag s toEnum :: Int -> SymTag s fromEnum :: SymTag s -> Int enumFrom :: SymTag s -> [SymTag s] enumFromThen :: SymTag s -> SymTag s -> [SymTag s] enumFromTo :: SymTag s -> SymTag s -> [SymTag s] enumFromThenTo :: SymTag s -> SymTag s -> SymTag s -> [SymTag s]
Eq (SymTag s) Source
Methods (==) :: SymTag s -> SymTag s -> Bool (/=) :: SymTag s -> SymTag s -> Bool
Ord (SymTag s) Source
Methods compare :: SymTag s -> SymTag s -> Ordering (<) :: SymTag s -> SymTag s -> Bool (<=) :: SymTag s -> SymTag s -> Bool (>) :: SymTag s -> SymTag s -> Bool (>=) :: SymTag s -> SymTag s -> Bool max :: SymTag s -> SymTag s -> SymTag s min :: SymTag s -> SymTag s -> SymTag s
Read (SymTag s) Source
Methods readsPrec :: Int -> ReadS (SymTag s) readList :: ReadS [SymTag s] readPrec :: ReadPrec (SymTag s) readListPrec :: ReadPrec [SymTag s]
Show (SymTag s) Source
Methods showsPrec :: Int -> SymTag s -> ShowS show :: SymTag s -> String showList :: [SymTag s] -> ShowS
KnownSymbol s => ToJSON (SymTag s) Source
Methods toJSON :: SymTag s -> Value
KnownSymbol s => FromJSON (SymTag s) Source
Methods parseJSON :: Value -> Parser (SymTag s)

Singleton object

newtype SingObject s a Source

Singleton value object

λ > decode "{\"value\": 42 }" :: Maybe (SingObject "value" Int)
Just (SingObject 42)

λ > encode (SingObject 42 :: SingObject "value" Int)
"{\"value\":42}"

Constructors

SingObject a

Instances

Functor (SingObject s) Source
Methods fmap :: (a -> b) -> SingObject s a -> SingObject s b (<$) :: a -> SingObject s b -> SingObject s a
Foldable (SingObject s) Source
Methods fold :: Monoid m => SingObject s m -> m foldMap :: Monoid m => (a -> m) -> SingObject s a -> m foldr :: (a -> b -> b) -> b -> SingObject s a -> b foldr' :: (a -> b -> b) -> b -> SingObject s a -> b foldl :: (b -> a -> b) -> b -> SingObject s a -> b foldl' :: (b -> a -> b) -> b -> SingObject s a -> b foldr1 :: (a -> a -> a) -> SingObject s a -> a foldl1 :: (a -> a -> a) -> SingObject s a -> a toList :: SingObject s a -> [a] null :: SingObject s a -> Bool length :: SingObject s a -> Int elem :: Eq a => a -> SingObject s a -> Bool maximum :: Ord a => SingObject s a -> a minimum :: Ord a => SingObject s a -> a sum :: Num a => SingObject s a -> a product :: Num a => SingObject s a -> a
Traversable (SingObject s) Source
Methods traverse :: Applicative f => (a -> f b) -> SingObject s a -> f (SingObject s b) sequenceA :: Applicative f => SingObject s (f a) -> f (SingObject s a) mapM :: Monad m => (a -> m b) -> SingObject s a -> m (SingObject s b) sequence :: Monad m => SingObject s (m a) -> m (SingObject s a)
Eq a => Eq (SingObject s a) Source
Methods (==) :: SingObject s a -> SingObject s a -> Bool (/=) :: SingObject s a -> SingObject s a -> Bool
Ord a => Ord (SingObject s a) Source
Methods compare :: SingObject s a -> SingObject s a -> Ordering (<) :: SingObject s a -> SingObject s a -> Bool (<=) :: SingObject s a -> SingObject s a -> Bool (>) :: SingObject s a -> SingObject s a -> Bool (>=) :: SingObject s a -> SingObject s a -> Bool max :: SingObject s a -> SingObject s a -> SingObject s a min :: SingObject s a -> SingObject s a -> SingObject s a
Read a => Read (SingObject s a) Source
Methods readsPrec :: Int -> ReadS (SingObject s a) readList :: ReadS [SingObject s a] readPrec :: ReadPrec (SingObject s a) readListPrec :: ReadPrec [SingObject s a]
Show a => Show (SingObject s a) Source
Methods showsPrec :: Int -> SingObject s a -> ShowS show :: SingObject s a -> String showList :: [SingObject s a] -> ShowS
(KnownSymbol s, ToJSON a) => ToJSON (SingObject s a) Source
Methods toJSON :: SingObject s a -> Value
(KnownSymbol s, FromJSON a) => FromJSON (SingObject s a) Source
Methods parseJSON :: Value -> Parser (SingObject s a)

mkSingObject :: Proxy s -> a -> SingObject s a Source

getSingObject :: Proxy s -> SingObject s a -> a Source

CollapsedList

newtype CollapsedList full elem Source

Collapsed list, singleton is represented as the value itself in JSON encoding.

λ > decode "null" :: Maybe (CollapsedList [Int] Int)
Just (CollapsedList [])
λ > decode "42" :: Maybe (CollapsedList [Int] Int)
Just (CollapsedList [42])
λ > decode "[1, 2, 3]" :: Maybe (CollapsedList [Int] Int)
Just (CollapsedList [1,2,3])

λ > encode (CollapsedList ([] :: [Int]))
"null"
λ > encode (CollapsedList ([42] :: [Int]))
"42"
λ > encode (CollapsedList ([1, 2, 3] :: [Int]))
"[1,2,3]"

Constructors

CollapsedList full

Instances

Eq full => Eq (CollapsedList full elem) Source
Methods (==) :: CollapsedList full elem -> CollapsedList full elem -> Bool (/=) :: CollapsedList full elem -> CollapsedList full elem -> Bool
Ord full => Ord (CollapsedList full elem) Source
Methods compare :: CollapsedList full elem -> CollapsedList full elem -> Ordering (<) :: CollapsedList full elem -> CollapsedList full elem -> Bool (<=) :: CollapsedList full elem -> CollapsedList full elem -> Bool (>) :: CollapsedList full elem -> CollapsedList full elem -> Bool (>=) :: CollapsedList full elem -> CollapsedList full elem -> Bool max :: CollapsedList full elem -> CollapsedList full elem -> CollapsedList full elem min :: CollapsedList full elem -> CollapsedList full elem -> CollapsedList full elem
Read full => Read (CollapsedList full elem) Source
Methods readsPrec :: Int -> ReadS (CollapsedList full elem) readList :: ReadS [CollapsedList full elem] readPrec :: ReadPrec (CollapsedList full elem) readListPrec :: ReadPrec [CollapsedList full elem]
Show full => Show (CollapsedList full elem) Source
Methods showsPrec :: Int -> CollapsedList full elem -> ShowS show :: CollapsedList full elem -> String showList :: [CollapsedList full elem] -> ShowS
(ToJSON elem, ToJSON full, ListLike full elem) => ToJSON (CollapsedList full elem) Source
Methods toJSON :: CollapsedList full elem -> Value
(FromJSON elem, FromJSON full, ListLike full elem) => FromJSON (CollapsedList full elem) Source
Methods parseJSON :: Value -> Parser (CollapsedList full elem)

getCollapsedList :: CollapsedList full elem -> full Source

parseCollapsedList :: (FromJSON elem, FromJSON full, ListLike full elem) => Object -> Text -> Parser full Source

Parses possibly collapsed array value from the object's field.

λ > newtype V = V [Int] deriving (Show)
λ > instance FromJSON V where parseJSON = withObject "V" $ \obj -> V <$> collapsedList obj "value"
λ > decode "{}" :: Maybe V
Just (V [])
λ > decode "{\"value\": null}" :: Maybe V
Just (V [])
λ > decode "{\"value\": 42}" :: Maybe V
Just (V [42])
λ > decode "{\"value\": [1, 2, 3, 4]}" :: Maybe V
Just (V [1,2,3,4])

Re-exports

module Data.Aeson.Compat