Derulo

Derulo parses and renders JSON simply. It aims to provide an RFC 7159 compliant parser and renderer without incurring any dependencies. It is intended to be used either for learning or in situations where dependencies are unwanted. In normal usage, prefer a faster, more robust library like Aeson.

Derulo does not export any identifiers that conflict with the prelude and can be imported unqualified.

>>> import Derulo

Use readJSON to parse a String into a JSON value.

>>> readJSON " null "
Just Null

Use showJSON to render a JSON value as a String.

>>> showJSON Null
"null"

Documentation

data JSON

A JSON value as described by RFC 7159.

Constructors

Null

Boolean Bool

Number Integer Integer

String String

Array [JSON]

Object [(String, JSON)]

Instances

Eq JSON

Defined in Derulo

Methods

(==) :: JSON -> JSON -> Bool

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

Data JSON

Defined in Derulo

Methods

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

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

toConstr :: JSON -> Constr

dataTypeOf :: JSON -> DataType

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

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

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

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

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

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

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

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

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

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

Ord JSON

Defined in Derulo

Methods

compare :: JSON -> JSON -> Ordering

(<) :: JSON -> JSON -> Bool

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

(>) :: JSON -> JSON -> Bool

(>=) :: JSON -> JSON -> Bool

max :: JSON -> JSON -> JSON

min :: JSON -> JSON -> JSON

Read JSON

Defined in Derulo

Methods

readsPrec :: Int -> ReadS JSON

readList :: ReadS [JSON]

readPrec :: ReadPrec JSON

readListPrec :: ReadPrec [JSON]

Show JSON

Defined in Derulo

Methods

showsPrec :: Int -> JSON -> ShowS

show :: JSON -> String

showList :: [JSON] -> ShowS

Generic JSON

Defined in Derulo

Associated Types

type Rep JSON :: * -> *

Methods

from :: JSON -> Rep JSON x

to :: Rep JSON x -> JSON

type Rep JSON

Defined in Derulo

type Rep JSON = D1 (MetaData "JSON" "Derulo" "derulo-1.0.3-EdL77rhFH7Y8SyYyfHFE52" False) ((C1 (MetaCons "Null" PrefixI False) (U1 :: * -> *) :+: (C1 (MetaCons "Boolean" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Bool)) :+: C1 (MetaCons "Number" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Integer) :*: S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Integer)))) :+: (C1 (MetaCons "String" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 String)) :+: (C1 (MetaCons "Array" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 [JSON])) :+: C1 (MetaCons "Object" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 [(String, JSON)])))))

readJSON :: String -> Maybe JSON

Parses a string as JSON.

>>> readJSON "null"
Just Null

>>> readJSON "true"
Just (Boolean True)
>>> readJSON "false"
Just (Boolean False)

>>> readJSON "0e0"
Just (Number 0 0)
>>> readJSON "12e34"
Just (Number 12 34)
>>> readJSON "-12e-34"
Just (Number (-12) (-34))

>>> readJSON "\"\""
Just (String "")
>>> readJSON "\"js\""
Just (String "js")
>>> readJSON "\"\\\"\\\\\\b\\f\\n\\r\\t\""
Just (String "\"\\\b\f\n\r\t")
>>> readJSON "\"\\u001f\""
Just (String "\US")

>>> readJSON "[]"
Just (Array [])
>>> readJSON "[null]"
Just (Array [Null])
>>> readJSON "[true,false]"
Just (Array [Boolean True,Boolean False])

>>> readJSON "{}"
Just (Object [])
>>> readJSON "{\"\":null}"
Just (Object [("",Null)])
>>> readJSON "{\"t\":true,\"f\":false}"
Just (Object [("t",Boolean True),("f",Boolean False)])

showJSON :: JSON -> String

Renders JSON as a string.

>>> showJSON Null
"null"

>>> showJSON (Boolean True)
"true"
>>> showJSON (Boolean False)
"false"

>>> showJSON (Number 0 0)
"0e0"
>>> showJSON (Number 12 34)
"12e34"
>>> showJSON (Number (-12) (-34))
"-12e-34"

>>> showJSON (String "")
"\"\""
>>> showJSON (String "js")
"\"js\""
>>> showJSON (String "\"\\\b\f\n\r\t")
"\"\\\"\\\\\\b\\f\\n\\r\\t\""
>>> showJSON (String "\x1f")
"\"\\u001f\""

>>> showJSON (Array [])
"[]"
>>> showJSON (Array [Null])
"[null]"
>>> showJSON (Array [Boolean True, Boolean False])
"[true,false]"

>>> showJSON (Object [])
"{}"
>>> showJSON (Object [("", Null)])
"{\"\":null}"
>>> showJSON (Object [("t", Boolean True), ("f", Boolean False)])
"{\"t\":true,\"f\":false}"