wtfjs

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# What the f\*ck JavaScript?

[![WTFPL 2.0][license-image]][license-url]
[![NPM version][npm-image]][npm-url]
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> A list of funny and tricky JavaScript examples

JavaScript is a great language. It has a simple syntax, large ecosystem and, what is most important, a great community.

At the same time, we all know that JavaScript is quite a funny language with tricky parts. Some of them can quickly turn our everyday job into hell, and some of them can make us laugh out loud.

The original idea for WTFJS belongs to [Brian Leroux](https://twitter.com/brianleroux). This list is highly inspired by his talk [**“WTFJS”** at dotJS 2012](https://www.youtube.com/watch?v=et8xNAc2ic8):

[![dotJS 2012 - Brian Leroux - WTFJS](https://img.youtube.com/vi/et8xNAc2ic8/0.jpg)](https://www.youtube.com/watch?v=et8xNAc2ic8)

# Node Packaged Manuscript

You can install this handbook using `npm`. Just run:

```
$ npm install -g wtfjs
```

You should be able to run `wtfjs` at the command line now. This will open the manual in your selected `$PAGER`. Otherwise, you may continue reading on here.

The source is available here: <https://github.com/denysdovhan/wtfjs>

# Translations

Currently, there are these translations of **wtfjs**:

- [中文](./README-zh-cn.md)
- [हिंदी](./README-hi.md)
- [Français](./README-fr-fr.md)
- [Português do Brasil](./README-pt-br.md)
- [Polski](./README-pl-pl.md)
- [Italiano](./README-it-it.md)
- [한국어](./README-kr.md)

[**Help translating to your language**][tr-request]

[tr-request]: https://github.com/denysdovhan/wtfjs/blob/master/CONTRIBUTING.md#translations

**Note:** Translations are maintained by their translators. They may not contain every example, and existing examples may be outdated.

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# Table of Contents

- [💪🏻 Motivation](#-motivation)
- [✍🏻 Notation](#-notation)
- [👀 Examples](#-examples)
  - [`[]` is equal `![]`](#-is-equal-)
  - [`true` is not equal `![]`, but not equal `[]` too](#true-is-not-equal--but-not-equal--too)
  - [true is false](#true-is-false)
  - [baNaNa](#banana)
  - [`NaN` is not a `NaN`](#nan-is-not-a-nan)
  - [`Object.is()` and `===` weird cases](#objectis-and--weird-cases)
  - [It's a fail](#its-a-fail)
  - [`[]` is truthy, but not `true`](#-is-truthy-but-not-true)
  - [`null` is falsy, but not `false`](#null-is-falsy-but-not-false)
  - [`document.all` is an object, but it is undefined](#documentall-is-an-object-but-it-is-undefined)
  - [Minimal value is greater than zero](#minimal-value-is-greater-than-zero)
  - [function is not a function](#function-is-not-a-function)
  - [Adding arrays](#adding-arrays)
  - [Trailing c