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Are these two values conceptually equal?
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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

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