Json (b0.B0_json.Json)

JSON text

type meta = B0_text.Textloc.t

The type for node metadata.

val meta_none : meta

meta_none is an invalid input location.

type 'a node = 'a * meta

Abstract syntax tree nodes.

type name = string node

The type for generic JSON object names.

type mem = name * t

The type for generic JSON object members.

and object' = mem list

The type for generic JSON objects.

and t =

| Null of unit node
| Bool of bool node
| Number of float node
(*
Encoders must use Null if float is not finite
*)
| String of string node
| Array of t list node
| Object of object' node
(*
The type for generic JSON text representations.
*)

val meta : t -> meta

meta j is j's node meta data.

val equal : t -> t -> bool

equal j0 j1 is compare j0 j1 = 0.

val compare : t -> t -> int

compare j0 j1 is a total order on JSON values:

Floating point values are compared with Float.compare, this means NaN values are equal.
Strings are compared byte wise.
Objects members are sorted before being compared.
meta values are ignored.

val normalize : t -> t

normalize j normalizes JSON j by sorting object's members by name using String.compare.

Constructors

type 'a cons = ?meta:meta -> 'a -> t

The type for constructing JSON values from an OCaml value of type 'a. meta default to meta_none.

Nulls and options

val null : unit cons

null is Null (unit, meta).

val option : 'a cons -> 'a option cons

null is Null (unit, meta).

Booleans

val bool : bool cons

bool b is Bool (b, meta).

Numbers

val number : float cons

number n is Number (b, meta).

val any_float : float cons

any_float v is number v if Float.is_finit v is true and string Float.to_string v otherwise.

Strings

val string : string cons

string s is `String (s, meta).

Arrays

val list : t list cons

list vs is Array (vs, meta).

val array : t array cons

array a is Array (Array.to_list a, meta).

Objects

val name : ?meta:meta -> string -> name

name ?meta n is n, meta. meta defaults to meta_none.

val mem : name -> t -> mem

mem n v is (name, v).

val object' : mem list cons

object' mems is Object (mems, meta).

Codec

val of_string : 
  ?file:B0_text.Textloc.filepath ->
  string ->
  (t, string) Stdlib.result

of_string s parses JSON text from s according to RFC8259 with the following limitations:

Numbers are parsed with string_of_float which is not compliant.

Note. All OCaml strings returned by this function are UTF-8 encoded.

val to_string : t -> string

to_string j is j as JSON text, encoded according to RFC8259.

Warning. Assumes all OCaml strings in j are UTF-8 encoded.

Formatters

type number_format =
  (float -> unit, Stdlib.Format.formatter, unit) Stdlib.format

The type for JSON number formatters.

val default_number_format : number_format

default_number_format is "%.17g". This number formats ensures that finite floating point values can be interchanged without loss of precision.

val pp' : 
  ?number_format:number_format ->
  unit ->
  Stdlib.Format.formatter ->
  t ->
  unit

pp' ~format ~number_format () ppf j formats j on ppf. The output is indented but may be more compact than an Indent JSON encoder may do. For example arrays may be output on one line if they fit etc.

number_format is used to format JSON numbers. Defaults to default_number_format
Non-finite numbers are output as JSON nulls (explanation).
Strings are assumed to be valid UTF-8.

val pp : Stdlib.Format.formatter -> t -> unit

pp formats JSON, see pp'.