fast-deep-equal

What is fast-deep-equal?

The fast-deep-equal package is a fast deep equality comparison library. It allows developers to check if two objects, arrays, or values are deeply equal to each other, meaning that their structure and nested values are identical.

What are fast-deep-equal's main functionalities?

Deep equality check for objects

This feature allows you to compare two objects to determine if they are deeply equal.

const equal = require('fast-deep-equal');
const obj1 = { a: 1, b: { c: 2 } };
const obj2 = { a: 1, b: { c: 2 } };
console.log(equal(obj1, obj2)); // true

Deep equality check for arrays

This feature allows you to compare two arrays to determine if they are deeply equal, including nested arrays.

const equal = require('fast-deep-equal');
const arr1 = [1, 2, [3, 4]];
const arr2 = [1, 2, [3, 4]];
console.log(equal(arr1, arr2)); // true

Deep equality check for values

This feature allows you to compare two primitive values to determine if they are equal.

const equal = require('fast-deep-equal');
const val1 = 'value';
const val2 = 'value';
console.log(equal(val1, val2)); // true

Other packages similar to fast-deep-equal

lodash.isequal

Lodash's isEqual function is a popular utility for performing deep equality checks. It is more feature-rich than fast-deep-equal, handling more edge cases and supporting customizer functions, but it may be slower for simple comparisons due to its comprehensive approach.

deep-equal

The deep-equal package provides a similar deep equality checking functionality. It is less performant than fast-deep-equal but offers a strict comparison mode that uses the === operator for equality checks.

nano-equal

Nano-equal is a minimalistic library for deep equality checks. It is designed to be small and fast, similar to fast-deep-equal, but may not handle as many edge cases.

README

fast-deep-equal

The fastest deep equal

Install

npm install fast-deep-equal

Features

• ES5 compatible
• works in node.js (0.10+) and browsers (IE9+)
• checks equality of Date and RegExp objects by value.

Usage

var equal = require('fast-deep-equal');
console.log(equal({foo: 'bar'}, {foo: 'bar'})); // true

Performance benchmark

fast-deep-equal x 82,915 ops/sec ±0.63% (89 runs sampled)
nano-equal x 50,506 ops/sec ±2.23% (86 runs sampled)
shallow-equal-fuzzy x 14,873 ops/sec ±3.19% (83 runs sampled)
underscore.isEqual x 16,055 ops/sec ±2.29% (85 runs sampled)
lodash.isEqual x 10,740 ops/sec ±1.04% (89 runs sampled)
deep-equal x 12,276 ops/sec ±2.44% (84 runs sampled)
deep-eql x 10,565 ops/sec ±0.89% (90 runs sampled)
assert.deepStrictEqual x 965 ops/sec ±2.99% (81 runs sampled)
The fastest is fast-deep-equal

To run benchmark (requires node.js 6+):

npm install
node benchmark

License

MIT