Module Kojson

module Kojson: sig .. end

Pattern Domains and Supporting Definitions.

Prerequisites

type json = [ `Assoc of (string * json) list
       | `Bool of bool
       | `Float of float
       | `Int of int
       | `List of json list
       | `Null
       | `String of string ]

The JSON tree, compatible with Yojson.Basic.json.

type path = [ `Index of int | `Label of string ] list

A path of crossed association labels and array indices, used to locate a pattern mismatch for better error reporting.

val string_of_path : path -> string

Convert a label and index path to a human readable string.

type expectation = [ `either of (path * expectation) list
       | `expecting_label of string
       | `expecting_type of string
       | `expecting_value of json
       | `expecting_values of json list
       | `not_expecting_labels of string list ]

Details of what was expected at the location where a pattern didn't match.

exception Mismatch of path * expectation

Exception raised to indicate a mismatch of a JSON value. The first parameter is a path leading up to the error, and the second parameter explains the expected value.

val string_of_mismatch : path * expectation -> string

Format a explanation of why a pattern did not match.

val default_warn : (path -> string -> unit) Pervasives.ref

This is the default warning handler used by Kojson.jin_of_json.

Pattern Domains

The following types form the domain of patterns, which can be built up from the definitions in Kojson_pattern.

type jin = Kojson_private.jin

A JSON value paired with a path and a custom warning callback to facilitate error reporting. A pattern is a function of type

jin ->
    'a

which throws Kojson.Mismatch if it does not match its argument.

val jin_of_json : ?warn:(path -> string -> unit) ->
       ?path:path -> json -> jin

Pair a JSON value with a path for use during matching.

warn : A callback to record warnings about unused labels. The default is Kojson.default_warn.

path : The root path of JSON tree, if not [].

val jin_path : jin -> path

type jain = Kojson_private.jain

A wrapper for an opened JSON association paired with a path and a custom warning callback to facility error reporting. An association pattern is a function of type jain -> 'a which throws Kojson.Mismatch if it does not match its argument.

val jain_path : jain -> path