json-0.10: Support for serialising Haskell to and from JSON

Safe Haskell | Safe
Language | Haskell98

Text.JSON.Types

Contents

- JSON Types
- Wrapper Types

Description

Basic support for working with JSON values.

Synopsis

- data JSValue
  - = JSNull
  - | JSBool !Bool
  - | JSRational Bool !Rational
  - | JSString JSString
  - | JSArray [JSValue]
  - | JSObject (JSObject JSValue)
- newtype JSString = JSONString {
  - fromJSString :: String
  }
- toJSString :: String -> JSString
- newtype JSObject e = JSONObject {
  - fromJSObject :: [(String, e)]
  }
- toJSObject :: [(String, a)] -> JSObject a
- get_field :: JSObject a -> String -> Maybe a
- set_field :: JSObject a -> String -> a -> JSObject a

# JSON Types

data JSValue Source #

JSON values

The type to which we encode Haskell values. There's a set of primitives, and a couple of heterogenous collection types.

Objects:

An object structure is represented as a pair of curly brackets surrounding zero or more name/value pairs (or members). A name is a string. A single colon comes after each name, separating the name from the value. A single comma separates a value from a following name.

Arrays:

An array structure is represented as square brackets surrounding zero or more values (or elements). Elements are separated by commas.

Only valid JSON can be constructed this way

Constructors

JSNull |
JSBool !Bool |
JSRational Bool !Rational |
JSString JSString |
JSArray [JSValue] |
JSObject (JSObject JSValue) |

#### Instances

Instances details

Eq JSValue Source # |
Instance details Defined in Text.JSON.Types Methods (==) :: JSValue -> JSValue -> Bool (/=) :: JSValue -> JSValue -> Bool
Ord JSValue Source # |
Instance details Defined in Text.JSON.Types Methods compare :: JSValue -> JSValue -> Ordering (<) :: JSValue -> JSValue -> Bool (<=) :: JSValue -> JSValue -> Bool (>) :: JSValue -> JSValue -> Bool (>=) :: JSValue -> JSValue -> Bool max :: JSValue -> JSValue -> JSValue min :: JSValue -> JSValue -> JSValue
Read JSValue Source # |
Instance details Defined in Text.JSON.Types Methods readsPrec :: Int -> ReadS JSValue readList :: ReadS [JSValue] readPrec :: ReadPrec JSValue readListPrec :: ReadPrec [JSValue]
Show JSValue Source # |
Instance details Defined in Text.JSON.Types Methods showsPrec :: Int -> JSValue -> ShowS show :: JSValue -> String showList :: [JSValue] -> ShowS
IsString JSValue Source # |
Instance details Defined in Text.JSON.Types Methods fromString :: String -> JSValue
JSON JSValue Source # | To ensure we generate valid JSON, we map Haskell types to JSValue internally, then pretty print that.
Instance details Defined in Text.JSON Methods readJSON :: JSValue -> Result JSValue Source # showJSON :: JSValue -> JSValue Source # readJSONs :: JSValue -> Result [JSValue] Source # showJSONs :: [JSValue] -> JSValue Source #

# Wrapper Types

newtype JSString Source #

Strings can be represented a little more efficiently in JSON

Constructors

JSONString |

Fields

- fromJSString :: String

#### Instances

Instances details

Eq JSString Source # |
Instance details Defined in Text.JSON.Types Methods (==) :: JSString -> JSString -> Bool (/=) :: JSString -> JSString -> Bool
Ord JSString Source # |
Instance details Defined in Text.JSON.Types Methods compare :: JSString -> JSString -> Ordering (<) :: JSString -> JSString -> Bool (<=) :: JSString -> JSString -> Bool (>) :: JSString -> JSString -> Bool (>=) :: JSString -> JSString -> Bool max :: JSString -> JSString -> JSString min :: JSString -> JSString -> JSString
Read JSString Source # |
Instance details Defined in Text.JSON.Types Methods readsPrec :: Int -> ReadS JSString readList :: ReadS [JSString] readPrec :: ReadPrec JSString readListPrec :: ReadPrec [JSString]
Show JSString Source # |
Instance details Defined in Text.JSON.Types Methods showsPrec :: Int -> JSString -> ShowS show :: JSString -> String showList :: [JSString] -> ShowS
IsString JSString Source # |
Instance details Defined in Text.JSON.Types Methods fromString :: String -> JSString
JSKey JSString Source # |
Instance details Defined in Text.JSON Methods toJSKey :: JSString -> String Source # fromJSKey :: String -> Maybe JSString Source #
JSON JSString Source # |
Instance details Defined in Text.JSON Methods readJSON :: JSValue -> Result JSString Source # showJSON :: JSString -> JSValue Source # readJSONs :: JSValue -> Result [JSString] Source # showJSONs :: [JSString] -> JSValue Source #

toJSString :: String -> JSString Source #

Turn a Haskell string into a JSON string.

newtype JSObject e Source #

As can association lists

Constructors

JSONObject |

Fields

- fromJSObject :: [(String, e)]

#### Instances

Instances details

Eq e => Eq (JSObject e) Source # |
Instance details Defined in Text.JSON.Types Methods (==) :: JSObject e -> JSObject e -> Bool (/=) :: JSObject e -> JSObject e -> Bool
Ord e => Ord (JSObject e) Source # |
Instance details Defined in Text.JSON.Types Methods compare :: JSObject e -> JSObject e -> Ordering (<) :: JSObject e -> JSObject e -> Bool (<=) :: JSObject e -> JSObject e -> Bool (>) :: JSObject e -> JSObject e -> Bool (>=) :: JSObject e -> JSObject e -> Bool max :: JSObject e -> JSObject e -> JSObject e min :: JSObject e -> JSObject e -> JSObject e
Read e => Read (JSObject e) Source # |
Instance details Defined in Text.JSON.Types Methods readsPrec :: Int -> ReadS (JSObject e) readList :: ReadS [JSObject e] readPrec :: ReadPrec (JSObject e) readListPrec :: ReadPrec [JSObject e]
Show e => Show (JSObject e) Source # |
Instance details Defined in Text.JSON.Types Methods showsPrec :: Int -> JSObject e -> ShowS show :: JSObject e -> String showList :: [JSObject e] -> ShowS
JSON a => JSON (JSObject a) Source # |
Instance details Defined in Text.JSON Methods readJSON :: JSValue -> Result (JSObject a) Source # showJSON :: JSObject a -> JSValue Source # readJSONs :: JSValue -> Result [JSObject a] Source # showJSONs :: [JSObject a] -> JSValue Source #

toJSObject :: [(String, a)] -> JSObject a Source #

Make JSON object out of an association list.

get_field :: JSObject a -> String -> Maybe a Source #

Get the value of a field, if it exist.

set_field :: JSObject a -> String -> a -> JSObject a Source #

Set the value of a field. Previous values are overwritten.