Convert a Value into a prettified string. The first argument specifies the amount of indentation in the resulting string.

import Json.Encode as Encode


tom : Encode.Value
tom =
    Encode.object
        [ ( "name", Encode.string "Tom" )
        , ( "age", Encode.int 42 )
        ]


compact = Encode.encode 0 tom
-- {"name":"Tom","age":42}


readable = Encode.encode 4 tom
-- {
--     "name": "Tom",
--     "age": 42
-- }

Represents a JavaScript value.

Turn a String into a JSON string.

import Json.Encode exposing (encode, string)


-- encode 0 (string "")      == "\"\""
-- encode 0 (string "abc")   == "\"abc\""
-- encode 0 (string "hello") == "\"hello\""

Turn an Int into a JSON number.

import Json.Encode exposing (encode, int)


-- encode 0 (int 42) == "42"
-- encode 0 (int -7) == "-7"
-- encode 0 (int 0)  == "0"

Turn a Float into a JSON number.

import Json.Encode exposing (encode, float)


-- encode 0 (float 3.14)     == "3.14"
-- encode 0 (float 1.618)    == "1.618"
-- encode 0 (float -42)      == "-42"
-- encode 0 (float NaN)      == "null"
-- encode 0 (float Infinity) == "null"

Note: Floating point numbers are defined in the IEEE 754 standard which is hardcoded into almost all CPUs. This standard allows Infinity and NaN. The JSON spec does not include these values, so we encode them both as null.

Turn a Bool into a JSON boolean.

import Json.Encode exposing (encode, bool)


-- encode 0 (bool True)  == "true"
-- encode 0 (bool False) == "false"

Create a JSON null value.

import Json.Encode exposing (encode, null)


-- encode 0 null == "null"

Turn a List into a JSON array.

import Json.Encode as Encode exposing (bool, encode, int, list, string)


-- encode 0 (list int [1,3,4])       == "[1,3,4]"
-- encode 0 (list bool [True,False]) == "[true,false]"
-- encode 0 (list string ["a","b"])  == """["a","b"]"""

Turn an Array into a JSON array.

Turn an Set into a JSON array.

Create a JSON object.

import Json.Encode as Encode


tom : Encode.Value
tom =
    Encode.object
        [ ( "name", Encode.string "Tom" )
        , ( "age", Encode.int 42 )
        ]


-- Encode.encode 0 tom == """{"name":"Tom","age":42}"""

Turn a Dict into a JSON object.

import Dict exposing (Dict)
import Json.Encode as Encode


people : Dict String Int
people =
  Dict.fromList [ ("Tom",42), ("Sue", 38) ]


-- Encode.encode 0 (Encode.dict identity Encode.int people)
--   == """{"Tom":42,"Sue":38}"""