node package manager
Easy collaboration. Discover, share, and reuse code in your team. Create a free org »


is-equal Version Badge

Build Status dependency status dev dependency status License Downloads

npm badge

browser support

Are these two values conceptually equal?


var isEqual = require('is-equal');
var assert = require('assert');
var primitives = [true, false, undefined, 42, 'foo'];
primitives.forEach(function (primitive) {
    assert.equal(isEqual(primitive, primitive), true);
assert.equal(isEqual(/a/g, /a/g));
assert.equal(isEqual(/a/g, new RegExp('a', 'g')));
assert.equal(isEqual({ a: 2 }, { a: 2 }), true);
assert.equal(isEqual([1, [2, 3], 4], [1, [2, 3], 4]), true);
var timestamp =;
assert.equal(isEqual(new Date(timestamp), new Date(timestamp)), true);

Want to know why two values are not equal?

Will return an empty string if isEqual would return true - otherwise will return a non-empty string that hopefully explains the reasoning.

var whyNotEqual = require('is-equal/why');
assert.equal(whyNotEqual(1, 1), '');
  whyNotEqual({ a: 1 }, { a: 2 }),
  'value at key "a" differs: numbers are different: 1 !== 2'


Simply clone the repo, npm install, and run npm test