Module `Ezjsonm`Source

An easy interface on top of the Jsonm library.

This version provides more convenient (but far less flexible) input and output functions that go to and from string values. This avoids the need to write signal code, which is useful for quick scripts that manipulate JSON.

More advanced users should go straight to the Jsonm library and use it directly, rather than be saddled with the Ezjsonm interface below.

Basic types

Sourcetype value = [

| `Null
| `Bool of bool
| `Float of float
| `String of string
| `A of value list
| `O of (string * value) list

]

JSON fragments.

Sourcetype t = [

| `A of value list
| `O of (string * value) list

]

Well-formed JSON documents.

Sourceval value : t -> value

Cast a JSON well-formed document into a JSON fragment.

Sourceval wrap : value -> [> t ]

wrap v wraps the value v into a JSON array. To use when it is not possible to statically know that v is a value JSON value.

Sourceval unwrap : t -> value

unwrap t is the reverse of wrap. It expects t to be a singleton JSON object and it return the unique element.

Reading JSON documents

Sourceval from_channel : in_channel -> [> t ]

Read a JSON document from an input channel.

Sourceval from_string : string -> [> t ]

Read a JSON document from a string.

Sourceval from_src : Jsonm.src -> [> t ]

Low-level function to read directly from a Jsonm source.

Writing JSON documents

Sourceval to_channel : ?minify:bool -> out_channel -> t -> unit

Write a JSON document to an output channel.

Sourceval to_buffer : ?minify:bool -> Buffer.t -> t -> unit

Write a JSON document to a buffer.

Sourceval to_string : ?minify:bool -> t -> string

Write a JSON document to a string. This goes via an intermediate buffer and so may be slow on large documents.

Sourceval to_dst : ?minify:bool -> Jsonm.dst -> t -> unit

Low-level function to write directly to a Jsonm destination.

Constructors

Sourceval unit : unit -> value

Same as `Null.

Sourceval bool : bool -> value

Same as `Bool b.

Sourceval string : string -> value

Same as `String s.

Sourceval strings : string list -> [> t ]

Same as `A [`String s1; ..; `String sn].

Sourceval int : int -> value

Same as `Float (float_of_int i).

Sourceval int32 : int32 -> value

Same as `Float (Int32.to_float i)

Sourceval int64 : int64 -> value

Same as `Float (Int64.to_float i)

Sourceval float : float -> value

Some as `Float f.

Sourceval list : ('a -> value) -> 'a list -> [> t ]

Build a list of values.

Sourceval option : ('a -> value) -> 'a option -> value

Either `Null or a JSON value.

Sourceval dict : (string * value) list -> [> t ]

Build a dictionnary.

Sourceval pair : ('a -> value) -> ('b -> value) -> ('a * 'b) -> [> t ]

Build a pair.

Source

val triple : 
  ('a -> value) ->
  ('b -> value) ->
  ('c -> value) ->
  ('a * 'b * 'c) ->
  [> t ]

Build a triple.

Accessors

Sourceexception Parse_error of value * string

All the following accessor functions expect the provided JSON document to be of a certain kind. In case this is not the case, Parse_error is raised.

Sourceval get_unit : value -> unit

Check that the JSON document is `Null.

Sourceval get_bool : value -> bool

Extract b from `Bool b.

Sourceval get_string : value -> string

Extract s from `String s.

Sourceval get_strings : value -> string list

Extract s1;..;sn from `A [`String s1; ...; `String sn].

Sourceval get_int : value -> int

Extract an integer.

Sourceval get_int32 : value -> int32

Extract a 32-bits integer.

Sourceval get_int64 : value -> int64

Extract a 64-bits integer.

Sourceval get_float : value -> float

Extract a float.

Sourceval get_list : (value -> 'a) -> value -> 'a list

Extract elements from a JSON array.

Sourceval get_option : (value -> 'a) -> value -> 'a option

Extract an optional document.

Sourceval get_dict : value -> (string * value) list

Extract the elements from a dictionnary document.

Sourceval get_pair : (value -> 'a) -> (value -> 'b) -> value -> 'a * 'b

Extract the pair.

Source

val get_triple : 
  (value -> 'a) ->
  (value -> 'b) ->
  (value -> 'c) ->
  value ->
  'a * 'b * 'c

Extract the triple.

High-level functions

Sourceval mem : value -> string list -> bool

Is the given path valid if the provided JSON document.

Sourceval find : value -> string list -> value

Find the sub-document adressed by the given path. Raise Not_found if the path is invalid.

Sourceval update : value -> string list -> value option -> value

Update the sub-document addressed by the given path. If the provided value is None, then removes the sub-document.

Sourceval map : (value -> value option) -> value -> string list -> value

Apply a given function to a subdocument.

Sourceval encode_string : string -> value

Convert a (possibly non-valid UTF8) string to a JSON object.

Sourceval decode_string : value -> string option

Convert a JSON object to a (possibly non-valid UTF8) string. Return None if the JSON object is not a valid string.

Sourceval decode_string_exn : value -> string

Convert a JSON object to a (possibly non-valid UTF8) string.

Sourceval to_sexp : value -> Sexplib.Type.t

Convert a JSON fragment to an S-expression.

Sourceval sexp_of_value : value -> Sexplib.Type.t

An alias of to_sexp

Sourceval sexp_of_t : t -> Sexplib.Type.t

Convert a JSON object to an S-expression

Sourceval of_sexp : Sexplib.Type.t -> value

Convert an S-expression to a JSON fragment

Sourceval value_of_sexp : Sexplib.Type.t -> value

AN alias of of_sexp

Sourceval t_of_sexp : Sexplib.Type.t -> t

Convert an S-expression to a JSON object

Error handling

Sourceval parse_error : value -> ('a, unit, string, 'b) format4 -> 'a

Raise Parse_error

package ezjsonm

Module EzjsonmSource