Data.Aeson.Lens

This module also exports orphan Ixed Value and Plated Value instances.

Numbers

class AsNumber t where

Minimal complete definition

Nothing

Methods

_Number :: Prism' t Scientific

>>> "[1, \"x\"]" ^? nth 0 . _Number
Just 1.0

>>> "[1, \"x\"]" ^? nth 1 . _Number
Nothing

_Number :: AsPrimitive t => Prism' t Scientific

>>> "[1, \"x\"]" ^? nth 0 . _Number
Just 1.0

>>> "[1, \"x\"]" ^? nth 1 . _Number
Nothing

_Double :: Prism' t Double

Prism into an Double over a Value, Primitive or Scientific

>>> "[10.2]" ^? nth 0 . _Double
Just 10.2

_Integer :: Prism' t Integer

Prism into an Integer over a Value, Primitive or Scientific

>>> "[10]" ^? nth 0 . _Integer
Just 10

>>> "[10.5]" ^? nth 0 . _Integer
Just 10

>>> "42" ^? _Integer
Just 42

Instances

AsNumber ByteString

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' ByteString Scientific

_Double :: Prism' ByteString Double

_Integer :: Prism' ByteString Integer

AsNumber ByteString

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' ByteString Scientific

_Double :: Prism' ByteString Double

_Integer :: Prism' ByteString Integer

AsNumber Scientific

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Scientific Scientific

_Double :: Prism' Scientific Double

_Integer :: Prism' Scientific Integer

AsNumber Text

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Text Scientific

_Double :: Prism' Text Double

_Integer :: Prism' Text Integer

AsNumber Value

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Value Scientific

_Double :: Prism' Value Double

_Integer :: Prism' Value Integer

AsNumber Text

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Text Scientific

_Double :: Prism' Text Double

_Integer :: Prism' Text Integer

AsNumber String

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' String Scientific

_Double :: Prism' String Double

_Integer :: Prism' String Integer

AsNumber Primitive

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Primitive Scientific

_Double :: Prism' Primitive Double

_Integer :: Prism' Primitive Integer

_Integral :: (AsNumber t, Integral a) => Prism' t a

Access Integer Values as Integrals.

>>> "[10]" ^? nth 0 . _Integral
Just 10

>>> "[10.5]" ^? nth 0 . _Integral
Just 10

nonNull :: Prism' Value Value

Prism into non-Null values

>>> "{\"a\": \"xyz\", \"b\": null}" ^? key "a" . nonNull
Just (String "xyz")

>>> "{\"a\": {}, \"b\": null}" ^? key "a" . nonNull
Just (Object (fromList []))

>>> "{\"a\": \"xyz\", \"b\": null}" ^? key "b" . nonNull
Nothing

Primitive

data Primitive

Primitives of Value

Constructors

StringPrim !Text

NumberPrim !Scientific

BoolPrim !Bool

NullPrim

Instances

Eq Primitive

Defined in Data.Aeson.Lens

Methods

(==) :: Primitive -> Primitive -> Bool

(/=) :: Primitive -> Primitive -> Bool

Data Primitive

Defined in Data.Aeson.Lens

Methods

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

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

toConstr :: Primitive -> Constr

dataTypeOf :: Primitive -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Primitive)

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

gmapT :: (forall b. Data b => b -> b) -> Primitive -> Primitive

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

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

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

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

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

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

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

Ord Primitive

Defined in Data.Aeson.Lens

Methods

compare :: Primitive -> Primitive -> Ordering

(<) :: Primitive -> Primitive -> Bool

(<=) :: Primitive -> Primitive -> Bool

(>) :: Primitive -> Primitive -> Bool

(>=) :: Primitive -> Primitive -> Bool

max :: Primitive -> Primitive -> Primitive

min :: Primitive -> Primitive -> Primitive

Show Primitive

Defined in Data.Aeson.Lens

Methods

showsPrec :: Int -> Primitive -> ShowS

show :: Primitive -> String

showList :: [Primitive] -> ShowS

AsPrimitive Primitive

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' Primitive Primitive

_String :: Prism' Primitive Text

_Bool :: Prism' Primitive Bool

_Null :: Prism' Primitive ()

AsNumber Primitive

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' Primitive Scientific

_Double :: Prism' Primitive Double

_Integer :: Prism' Primitive Integer

class AsNumber t => AsPrimitive t where

Minimal complete definition

Nothing

Methods

_Primitive :: Prism' t Primitive

>>> "[1, \"x\", null, true, false]" ^? nth 0 . _Primitive
Just (NumberPrim 1.0)

>>> "[1, \"x\", null, true, false]" ^? nth 1 . _Primitive
Just (StringPrim "x")

>>> "[1, \"x\", null, true, false]" ^? nth 2 . _Primitive
Just NullPrim

>>> "[1, \"x\", null, true, false]" ^? nth 3 . _Primitive
Just (BoolPrim True)

>>> "[1, \"x\", null, true, false]" ^? nth 4 . _Primitive
Just (BoolPrim False)

_Primitive :: AsValue t => Prism' t Primitive

>>> "[1, \"x\", null, true, false]" ^? nth 0 . _Primitive
Just (NumberPrim 1.0)

>>> "[1, \"x\", null, true, false]" ^? nth 1 . _Primitive
Just (StringPrim "x")

>>> "[1, \"x\", null, true, false]" ^? nth 2 . _Primitive
Just NullPrim

>>> "[1, \"x\", null, true, false]" ^? nth 3 . _Primitive
Just (BoolPrim True)

>>> "[1, \"x\", null, true, false]" ^? nth 4 . _Primitive
Just (BoolPrim False)

_String :: Prism' t Text

>>> "{\"a\": \"xyz\", \"b\": true}" ^? key "a" . _String
Just "xyz"

>>> "{\"a\": \"xyz\", \"b\": true}" ^? key "b" . _String
Nothing

>>> _Object._Wrapped # [("key" :: Text, _String # "value")] :: String
"{\"key\":\"value\"}"

_Bool :: Prism' t Bool

>>> "{\"a\": \"xyz\", \"b\": true}" ^? key "b" . _Bool
Just True

>>> "{\"a\": \"xyz\", \"b\": true}" ^? key "a" . _Bool
Nothing

>>> _Bool # True :: String
"true"

>>> _Bool # False :: String
"false"

_Null :: Prism' t ()

>>> "{\"a\": \"xyz\", \"b\": null}" ^? key "b" . _Null
Just ()

>>> "{\"a\": \"xyz\", \"b\": null}" ^? key "a" . _Null
Nothing

>>> _Null # () :: String
"null"

Instances

AsPrimitive ByteString

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' ByteString Primitive

_String :: Prism' ByteString Text

_Bool :: Prism' ByteString Bool

_Null :: Prism' ByteString ()

AsPrimitive ByteString

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' ByteString Primitive

_String :: Prism' ByteString Text

_Bool :: Prism' ByteString Bool

_Null :: Prism' ByteString ()

AsPrimitive Text

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' Text Primitive

_String :: Prism' Text Text

_Bool :: Prism' Text Bool

_Null :: Prism' Text ()

AsPrimitive Value

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' Value Primitive

_String :: Prism' Value Text

_Bool :: Prism' Value Bool

_Null :: Prism' Value ()

AsPrimitive Text

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' Text Primitive

_String :: Prism' Text Text0

_Bool :: Prism' Text Bool

_Null :: Prism' Text ()

AsPrimitive String

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' String Primitive

_String :: Prism' String Text

_Bool :: Prism' String Bool

_Null :: Prism' String ()

AsPrimitive Primitive

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' Primitive Primitive

_String :: Prism' Primitive Text

_Bool :: Prism' Primitive Bool

_Null :: Prism' Primitive ()

Objects and Arrays

class AsPrimitive t => AsValue t where

Minimal complete definition

_Value

Methods

_Value :: Prism' t Value

>>> preview _Value "[1,2,3]" == Just (Array (Vector.fromList [Number 1.0,Number 2.0,Number 3.0]))
True

_Object :: Prism' t (HashMap Text Value)

>>> "{\"a\": {}, \"b\": null}" ^? key "a" . _Object
Just (fromList [])

>>> "{\"a\": {}, \"b\": null}" ^? key "b" . _Object
Nothing

>>> _Object._Wrapped # [("key" :: Text, _String # "value")] :: String
"{\"key\":\"value\"}"

_Array :: Prism' t (Vector Value)

>>> preview _Array "[1,2,3]" == Just (Vector.fromList [Number 1.0,Number 2.0,Number 3.0])
True

Instances

AsValue ByteString

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' ByteString Value

_Object :: Prism' ByteString (HashMap Text Value)

_Array :: Prism' ByteString (Vector Value)

AsValue ByteString

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' ByteString Value

_Object :: Prism' ByteString (HashMap Text Value)

_Array :: Prism' ByteString (Vector Value)

AsValue Text

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' Text Value

_Object :: Prism' Text (HashMap Text Value)

_Array :: Prism' Text (Vector Value)

AsValue Value

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' Value Value

_Object :: Prism' Value (HashMap Text Value)

_Array :: Prism' Value (Vector Value)

AsValue Text

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' Text Value

_Object :: Prism' Text (HashMap Text0 Value)

_Array :: Prism' Text (Vector Value)

AsValue String

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' String Value

_Object :: Prism' String (HashMap Text Value)

_Array :: Prism' String (Vector Value)

key :: AsValue t => Text -> Traversal' t Value

Like ix, but for Value with Text indices. This often has better inference than ix when used with OverloadedStrings.

>>> "{\"a\": 100, \"b\": 200}" ^? key "a"
Just (Number 100.0)

>>> "[1,2,3]" ^? key "a"
Nothing

members :: AsValue t => IndexedTraversal' Text t Value

An indexed Traversal into Object properties

>>> Data.List.sort ("{\"a\": 4, \"b\": 7}" ^@.. members . _Number)
[("a",4.0),("b",7.0)]

>>> "{\"a\": 4}" & members . _Number *~ 10
"{\"a\":40}"

nth :: AsValue t => Int -> Traversal' t Value

Like ix, but for Arrays with Int indexes

>>> "[1,2,3]" ^? nth 1
Just (Number 2.0)

>>> "{\"a\": 100, \"b\": 200}" ^? nth 1
Nothing

>>> "[1,2,3]" & nth 1 .~ Number 20
"[1,20,3]"

values :: AsValue t => IndexedTraversal' Int t Value

An indexed Traversal into Array elements

>>> "[1,2,3]" ^.. values
[Number 1.0,Number 2.0,Number 3.0]

>>> "[1,2,3]" & values . _Number *~ 10
"[10,20,30]"

Decoding

class AsJSON t where

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism t t a b

_JSON is a Prism from something containing JSON to something encoded in that structure

Instances

AsJSON ByteString

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism ByteString ByteString a b

AsJSON ByteString

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism ByteString ByteString a b

AsJSON Text

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism Text Text a b

AsJSON Value

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism Value Value a b

AsJSON Text

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism Text Text a b

AsJSON String

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON b) => Prism String String a b

_JSON' :: (AsJSON t, FromJSON a, ToJSON a) => Prism' t a

Pattern Synonyms

pattern JSON :: (FromJSON a, ToJSON a, AsJSON t) => a -> t

pattern Value_ :: (FromJSON a, ToJSON a) => a -> Value

pattern Number_ :: AsNumber t => Scientific -> t

pattern Double :: AsNumber t => Double -> t

pattern Integer :: AsNumber t => Integer -> t

pattern Integral :: (AsNumber t, Integral a) => a -> t

pattern Primitive :: AsPrimitive t => Primitive -> t

pattern Bool_ :: AsPrimitive t => Bool -> t

pattern String_ :: AsPrimitive t => Text -> t

pattern Null_ :: AsPrimitive t => t

Orphan instances

Ixed Value

Methods

ix :: Index Value -> Traversal' Value (IxValue Value)

Plated Value

Methods

plate :: Traversal' Value Value