Z.Data.JSON.Builder

This module provides builders for JSON Values, a Haskell JSON representation. These builders are designed to comply with rfc8258. Only control characters are escaped, other unicode codepoints are directly written instead of being escaped.

Value Builders

value :: Value -> Builder ()

Encode a Value, you can use this function with toValue to get encodeJSON with a small overhead.

object :: Vector (Text, Value) -> Builder ()

object' :: (a -> Builder ()) -> Vector (Text, a) -> Builder ()

array :: Vector Value -> Builder ()

array' :: (a -> Builder ()) -> Vector a -> Builder ()

string :: Text -> Builder ()

Escape text into JSON string and add double quotes, escaping rules:

   '\b':  "\b"
   '\f':  "\f"
   '\n':  "\n"
   '\r':  "\r"
   '\t':  "\t"
   '"':  "\""
   '\':  "\\"
   'DEL':  "\u007f"
   other chars <= 0x1F: "\u00XX"

prettyValue :: Value -> Builder ()

'ValuePretty'' with 4 spaces indentation per level, e.g.

{
    "results":
    [
        {
            "from_user_id_str":"80430860",
            "profile_image_url":"http://a2.twimg.com/profile_images/536455139/icon32_normal.png",
            "created_at":"Wed, 26 Jan 2011 07:07:02 +0000",
            "from_user":"kazu_yamamoto",
            "id_str":"30159761706061824",
            "metadata":
            {
                "result_type":"recent"
            },
            "to_user_id":null,
            "text":"Haskell Server Pages って、まだ続いていたのか！",
            "id":30159761706061824,
            "from_user_id":80430860,
            "geo":null,
            "iso_language_code":"no",
            "to_user_id_str":null,
            "source":"<a href="http:/twitter.com">web</a>"
        }
    ],
    "max_id":30159761706061824,
    "since_id":0,
    "refresh_url":"?since_id=30159761706061824&q=haskell",
    "next_page":"?page=2&max_id=30159761706061824&rpp=1&q=haskell",
    "results_per_page":1,
    "page":1,
    "completed_in":1.2606e-2,
    "since_id_str":"0",
    "max_id_str":"30159761706061824",
    "query":"haskell"
}

prettyValue'

Arguments

:: Int

indentation per level

-> Int

initial indentation

-> Value

-> Builder ()

Encode a Value with indentation and linefeed.

Builder helpers

kv :: Text -> Builder () -> Builder ()

Use : as separator to connect a label(no escape, only add quotes) with field builders.

Don't use chars which need escaped in label.

kv' :: Text -> Builder () -> Builder ()

Use : as separator to connect a label(escape the label and add quotes) with field builders.

Re-export Value type

data Value

A JSON value represented as a Haskell value.

The Object's payload is a key-value vector instead of a map, which parsed directly from JSON document. This design choice has following advantages:

• Allow different strategies handling duplicated keys.
• Allow different Map type to do further parsing, e.g. FlatMap
• Roundtrip without touching the original key-value order.
• Save time if constructing map is not neccessary, e.g. using a linear scan to find a key if only that key is needed.

Constructors

Object !(Vector (Text, Value))

Array !(Vector Value)

String !Text

Number !Scientific

Bool !Bool

Null

Instances

Eq Value

Defined in Z.Data.JSON.Value

Methods

(==) :: Value -> Value -> Bool

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

Ord Value

Defined in Z.Data.JSON.Value

Methods

compare :: Value -> Value -> Ordering

(<) :: Value -> Value -> Bool

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

(>) :: Value -> Value -> Bool

(>=) :: Value -> Value -> Bool

max :: Value -> Value -> Value

min :: Value -> Value -> Value

Show Value

Defined in Z.Data.JSON.Value

Methods

showsPrec :: Int -> Value -> ShowS

show :: Value -> String

showList :: [Value] -> ShowS

Generic Value

Defined in Z.Data.JSON.Value

Associated Types

type Rep Value :: Type -> Type

Methods

from :: Value -> Rep Value x

to :: Rep Value x -> Value

Arbitrary Value

Defined in Z.Data.JSON.Value

Methods

arbitrary :: Gen Value

shrink :: Value -> [Value]

NFData Value

Defined in Z.Data.JSON.Value

Methods

rnf :: Value -> ()

Print Value

Defined in Z.Data.JSON.Value

Methods

toUTF8BuilderP :: Int -> Value -> Builder ()

JSON Value

Defined in Z.Data.JSON.Base

Methods

fromValue :: Value -> Converter Value

toValue :: Value -> Value

encodeJSON :: Value -> Builder ()

type Rep Value

Defined in Z.Data.JSON.Value

type Rep Value = D1 ('MetaData "Value" "Z.Data.JSON.Value" "Z-Data-0.8.3.0-37u7OlWXbeeLJtWSrSJkMP" 'False) ((C1 ('MetaCons "Object" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'SourceUnpack 'SourceStrict 'DecidedStrict) (Rec0 (Vector (Text, Value)))) :+: (C1 ('MetaCons "Array" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'SourceUnpack 'SourceStrict 'DecidedStrict) (Rec0 (Vector Value))) :+: C1 ('MetaCons "String" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'SourceUnpack 'SourceStrict 'DecidedStrict) (Rec0 Text)))) :+: (C1 ('MetaCons "Number" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'SourceUnpack '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))))