is-nan

is-nan

ES2015-compliant shim for Number.isNaN - the global isNaN returns false positives.

This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the spec.

Example

Number.isNaN = require('is-nan');
var assert = require('assert');

assert.notOk(Number.isNaN(undefined));
assert.notOk(Number.isNaN(null));
assert.notOk(Number.isNaN(false));
assert.notOk(Number.isNaN(true));
assert.notOk(Number.isNaN(0));
assert.notOk(Number.isNaN(42));
assert.notOk(Number.isNaN(Infinity));
assert.notOk(Number.isNaN(-Infinity));
assert.notOk(Number.isNaN('foo'));
assert.notOk(Number.isNaN(function () {}));
assert.notOk(Number.isNaN([]));
assert.notOk(Number.isNaN({}));

assert.ok(Number.isNaN(NaN));

Tests

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

Similar packages

Other packages similar to is-nan

lodash.isnan

Lodash provides a method called _.isNaN which is similar to is-nan. It checks if a value is NaN. Lodash's implementation is part of a larger utility library, which means it might be preferable if you're already using Lodash in your project.

number-is-nan

This package offers a polyfill for Number.isNaN, which is a standard method introduced in ES6. It is similar to is-nan but is specifically a polyfill for the Number.isNaN function, which is not available in older environments.