deep-is

What is deep-is?

The deep-is npm package provides a utility function for performing deep equality checks between two values. It can be used to determine if two objects, arrays, or other nested structures have the same content, regardless of whether they are the same reference in memory.

What are deep-is's main functionalities?

Deep Equality Check

This feature allows you to compare two complex objects or arrays to determine if they are deeply equal, meaning that their structure and values are the same, even if they are different instances in memory.

var deepEqual = require('deep-is');
console.log(deepEqual({ a: 1, b: { c: 1 } }, { a: 1, b: { c: 1 } })); // true
console.log(deepEqual([1, 2, [3, 4]], [1, 2, [3, 4]])); // true
console.log(deepEqual({ a: 1, b: { c: 1 } }, { a: 1, b: { c: 2 } })); // false

Other packages similar to deep-is

lodash.isequal

Lodash provides a method called isEqual which performs a deep comparison between two values to determine if they are equivalent. It handles a wide variety of data types and is known for its performance and reliability. Compared to deep-is, lodash is a larger library with many more utility functions, but lodash.isequal can be used independently.

fast-deep-equal

fast-deep-equal is a package that offers a fast deep equality comparison algorithm. It claims to be the fastest library for deep equality checks. Unlike deep-is, fast-deep-equal focuses solely on performance and may be a better choice for performance-critical applications.

deep-equal

deep-equal is another npm package that provides functionality similar to deep-is. It offers strict and non-strict comparison modes and can handle circular references. While deep-is is minimalistic and straightforward, deep-equal provides additional options for comparison customization.

README

deep-is

Node's assert.deepEqual() algorithm as a standalone module. Exactly like deep-equal except for the fact that deepEqual(NaN, NaN) === true.

This module is around 5 times faster than wrapping assert.deepEqual() in a try/catch.

example

var equal = require('deep-is');
console.dir([
    equal(
        { a : [ 2, 3 ], b : [ 4 ] },
        { a : [ 2, 3 ], b : [ 4 ] }
    ),
    equal(
        { x : 5, y : [6] },
        { x : 5, y : 6 }
    )
]);

methods

var deepIs = require('deep-is')

deepIs(a, b)

Compare objects a and b, returning whether they are equal according to a recursive equality algorithm.

install

With npm do:

npm install deep-is

test

With npm do:

npm test

license

Copyright (c) 2012, 2013 Thorsten Lorenz [e-mail] Copyright (c) 2012 James Halliday [e-mail]

Derived largely from node's assert module, which has the copyright statement:

Copyright (c) 2009 Thomas Robinson <280north.com>

Released under the MIT license, see LICENSE for details.