is-negative-zero

is-negative-zero

Is this value negative zero? === will lie to you.

Example

var isNegativeZero = require('is-negative-zero');
var assert = require('assert');

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

assert.ok(isNegativeZero(-0));

Tests

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

Changelog

v2.0.3 - 2024-02-19

Commits

• add types e28f0d5
• [meta] use npmignore to autogenerate an npmignore file f68ec13
• [Dev Deps] update eslint, @ljharb/eslint-config, aud, auto-changelog, tape 70abff7
• [actions] update rebase action to use reusable workflow 6e1356e
• [Dev Deps] update @ljharb/eslint-config, aud, npmignore, tape c00d4ab
• [meta] add sideEffects flag 9c45539

Similar packages

Other packages similar to is-negative-zero

is-zero

Similar to is-negative-zero, is-zero is a utility for checking if a number is 0. However, it does not distinguish between -0 and +0, making it less specific for cases where the sign of zero matters.

lodash.isequal

While not specifically designed for checking -0, lodash's isEqual function can accurately compare -0 and +0, among many other complex equality checks. It's more versatile but also much larger and more complex than is-negative-zero, which is focused solely on the -0 check.