Package Exports

json8
json8/lib/clone
json8/lib/equal
json8/lib/isJSON
json8/lib/type

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (json8) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

JSON8

Introduction

JSON8 is a JavaScript library that makes working with JSON/data/structures safer and easier.

Features

Strong JSON and type validation
Full support for Map and Set
Support Node.js/io.js and browsers; es5-shim for < IE 9, JSON polyfill for < IE 8
Smarter and safer JSON serializer/stringify
See Methods and Motivations
Tested
Small, no dependencies
Modular, save bandwith/memory by requiring needed methods using require('json8/lib/METHOD_NAME')

Getting started

npm install json8

var oo = require('json8');

<script src="node_modules/json8/JSON8.js"></script>

var oo = window.JSON8

↑

Methods

oo.clone

Deep clone any value.

var doc = {"foo": "bar"}
var clone = oo.clone(doc) // {"foo":"bar"}
doc === copy        // false
oo.equal(doc, copy) // true

oo.clone(true) // true
oo.clone(42)   // 42
oo.clone(-0)   // -0

↑

oo.equal

Test for equality between two documents.

oo.equal(true, true)     // true
oo.equal([], [])         // true
oo.equal({}, {})         // true
oo.equal(
  {foo: 'bar', bar: 'foo'}
  {bar: 'foo', foo: 'bar'}
)                        // true
oo.equal(new Set([1, 2]), new Set([1, 2])) // true
oo.equal(new Set([2, 1]), new Set([1, 2])) // false

oo.equal(new Set(), []) // true
oo.equal(new Map(), {}) // true

oo.equal([1, 2], [2, 1]) // false

oo.equal(-0, +0) // false

↑

oo.type

Returns the JSON type for a value, undefined if the value is not of any JSON type.

oo.type({})        // 'object'
oo.type(new Map()) // 'object'
oo.type([])        // 'array'
oo.type(new Set()) // 'array'
oo.type(42)        // 'number'
oo.type('foo')     // 'string'
oo.type(null)      // 'null'
oo.type(true)      // 'boolean'

oo.type(undefined)      // undefined
oo.type(Infinity)       // undefined
oo.type(-Infinity)      // undefined
oo.type(NaN)            // undefined
oo.type(Symbol())       // undefined
oo.type(function() {})  // undefined

↑

oo.is

For each type you can use the syntax

oo.is('foo', type)

oo.isType('foo')

Where type is any of:

structure
primitive
object
array
number
string
boolean
null
JSON

structure

Returns true for arrays and objects, false otherwise.

oo.is({}, 'structure')    // true
oo.isStructure([])        // true
oo.isStructure(new Set()) // true
oo.isStructure(new Map()) // true

oo.isStructure(null)   // false

↑

primitive

Returns true for primitives, false otherwise. Primitives are: number, boolean, null, string.

oo.is(null, 'primitive') // true
oo.isPrimitive(true)     // true
oo.isPrimitive('foo')    // true
oo.isPrimitive(42)       // true

oo.isPrimitive([]])      // false
oo.isPrimitive({})       // false
oo.isPrimitive(Infinity) // false
oo.isPrimitive(NaN)      // false

↑

object

Returns true for object, false otherwise.

oo.is({}, 'object')        // true
oo.isObject({})            // true
oo.isObject(new Map())     // true

oo.isObject(null)          // false
oo.isObject([])            // false
oo.isObject(null)          // false
oo.isObject(function() {}) // false
oo.isObject(new Set())     // false

↑

array

Returns true for array, false otherwise.

oo.is([], 'array')    // true
oo.isArray([])        // true
oo.isArray(new Set()) // true

oo.isArray({})        // false
oo.isArray(new Map()) // false

↑

number

Returns true for number, false otherwise.

oo.is(42, 'number')    // true
oo.isNumber(4.2)       // true
oo.isNumber(-42)       // true

oo.isNumber(Infinity)  // false; Infinity is not valid JSON
oo.isNumber(-Infinity) // false; -Infinity is not valid JSON
oo.isNumber(NaN)       // false; NaN is not valid JSON

↑

string

Returns true for string, false otherwise.

oo.is('foo', 'string') // true
oo.isString('☕'️)       // true
oo.isString('')        // true

oo.isString(42)        // false
oo.isString(undefined) // false
oo.isString(null)      // false

↑

boolean

Returns true for boolean, false otherwise.

oo.is(true, 'boolean') // true
oo.isBoolean(false)    // true

oo.isBoolean(0)        // false
oo.isBoolean('foo')    // false

↑

null

Returns true for null, false otherwise.

oo.is(null, 'null')  // true
oo.isNull(null)      // true

oo.isNull(undefined) // false

↑

JSON

Returns true for any JSON valid value. JSON valid values are: number, boolean, null, string, array, object.

This method is not recursive, if you need to deep check for validity use the valid method.

oo.is(true, 'JSON')      //true
oo.isJSON('foo')         //true
oo.isJSON(null)          //true
oo.isJSON({})            //true
oo.isJSON([])            //true
oo.isJSON(42)            //true
oo.isJSON(new Map())     //true
oo.isJSON(new Set())     //true

oo.isJSON(undefined)     //false
oo.isJSON(NaN)           //false
oo.isJSON(Infinity)      //false
oo.isJSON(-Infinity)     //false
oo.isJSON(function() {}) //false

↑

oo.valid

Recursive version of is JSON, works on primitive values as well.

oo.valid(true)                   //true
oo.valid({"foo": "bar"})         //true

oo.valid({"foo": undefined})     //false
oo.valid({"foo": NaN})           //false
oo.valid(["bar", function() {}]) //false

↑

oo.serialize

Takes a JSON document and returns a parseable JSON string. Uses JSON.stringify underneath so it's still fast.

Differences with JSON.stringify

Throws a TypeError for any invalid JSON value encountered such as
- undefined
- Infinity
- -Infinity
- NaN
- symbols
- functions
Works with Map (serialized as JSON object)
Works with Set (serialized as JSON array)
Serializes signed zeros -0 as "-0" while JSON.stringify returns "0"
Options are provided as an object instead of arguments

Options

toJSON set to false disable toJSON behavior (defaults to true)
space same as JSON.stringify space argument
replacer same as JSON.stringify replacer argument but remove the value from the array if undefined is returned

oo.serialize(doc[, options]);

oo.serialize({"foo": "bar"})
// {"foo":"bar"}

/*
 * Set serialization
 */
var set = new Set()
set.add('hello')
oo.serialize(set)
// ["hello"]

/*
 * Map serialization
 */
var map = new Map()
map.set('foo', 'bar')
oo.serialize(map)
// {"foo":"bar"}

/*
 * toJSON option
 */
oo.serialize(new Date())
// "2015-10-21T16:29:00.000Z"
oo.serialize(new Date(), {toJSON: false})
// {}

/*
 * space option
 */
var obj = {foo: 'bar'}
oo.serialize(obj)
// {"foo":"bar"}
oo.serialize(obj, {space: 2})
// {
//   "foo": "bar"
// }

↑

oo.parse

Takes a JSON string and returns a JavaScript value.

var doc = oo.parse(string[, options]);

options.set to parse JSON arrays as Set (default false). options.map to parse JSON objects as Map (default false).

↑

Motivations

Types

Getting/asserting the JSON type of a value in JavaScript is troublesome.

oo.type returns the JSON type of any value
oo.is checks if a value is of the provided type
oo.isStructure checks if a value is a JSON structure (an array or an object)
oo.isPrimitive checks if a value is a JSON primitive (null, boolean, string, number)
oo.isJSON checks if the value is a JSON valid value

↑

Safety

oo.serialize will throw an exception for any non JSON valid value (undefined, NaN, Infinity, -Infinity, ...) instead of ignoring it or replacing it with null like JSON.striginfy does. It also accept an optional argument to disable toJSON behavior which is a common pitfall.

JSON8 types helps avoiding many common errors as well.

oo.equal performs a deep JSON equality comparaison

oo.valid performs a recursive JSON validation on any value

↑

Map and Set

Map and Set are new structures available in ES6. Both are serializable and parseable as JSON, Map as object and Set as array. JSON8 was designed with that in mind and every single method supports Map and Set, a few examples:

isArray returns true for Set
isObject returns true for Map
valid, isStructure, isJSON return true for Map and Set
type returns 'array' for Set and 'object' for Map
serialize stringifies Set as array and Map as object
parse optionally parses arrays as Set and objects as Map

↑

Comparaisons

// undefined is not JSON valid
JSON.stringify(undefined) // undefined
oo.serialize(undefined)   // TypeError

JSON.stringify({foo: undefined}) // '{}'
oo.serialize({foo: undefined})   // TypeError

JSON.stringify([undefined]) // '[null]'
oo.serialize([undefined])   // TypeError

// same applies for NaN, Infinity and -Infinity
typeof NaN   // 'number'
oo.type(NaN) // undefined

JSON.stringify(NaN)        // 'null'
JSON.stringify({foo: NaN}) // '{"foo":null}'
JSON.stringify([NaN])      // '[null]'
oo.serialize(NaN)          // TypeError

// typeof null returns 'object'
typeof null   // 'object'
oo.type(null) // 'null'

// arrays
var array = []
typeof []      // 'object'
oo.type(array) // 'array'
array[2] = 'foo'
array[1]              // undefined
array[0]              // undefined
JSON.stringify(array) // '[null,null,"foo"]'
oo.serialize(array)   // TypeError

// functions
JSON.stringify(function(){})        // undefined
JSON.stringify({foo: function(){}}) // '{}'
JSON.stringify([function(){}])      // '[null]'
oo.serialize(function() {})         // TypeError

// Set
var set = new Set()
typeof set   // 'object'
oo.type(set) // 'array'

set.add('foo')
JSON.stringify(set) // '{}'
oo.serialize(set)   // '["foo"]'

// Map
var map = new Map()
typeof map   // 'object'
oo.type(map) // 'object'

map.set('foo', 'bar')
JSON.stringify(map) // '{}'
oo.serialize(map)   // '{"foo": "bar"}'

// typeof Date returns 'object' but JSON.stringify returns a string
typeof new Date()                         // 'object'
JSON.stringify(new Date())                // '2015-10-21T16:29:00.000Z'
oo.type(new Date())                       // 'object'
oo.serialize(new Date(), {toJSON: false}) // '{}'
oo.serialize(new Date())                  // '2015-10-21T16:29:00.000Z'

// -0
-0 === 0           //  true
oo.equal(-0, 0)    //  false

JSON.parse("-0")   //  -0
JSON.stringify(-0) //  "0"

oo.parse("-0")     //  -0
oo.serialize(-0)   // "-0"

↑

Tests

npm install -g mocha babel browserify
npm test

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Contributing

See CONTRIBUTING.md

↑