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https://github.com/joelnet/nothis

The complete elimination and eradication of JavaScript's this.
https://github.com/joelnet/nothis

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The complete elimination and eradication of JavaScript's this.

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# NO. THIS.

The complete elimination and eradication of JavaScript's _this_.

![nothis demo](https://github.com/joelnet/nothis/raw/master/assets/nothis.gif)

If _this_ is so difficult to reason about, why don't we just stop using it? Seriously. **Why. don't. we. just. stop. using. it.**?

When a function is decorated with the `nothis` function decorator it will pass `this` as the first argument. [Read more on function decorators here](https://dev.to/joelnet/function-decorators-part-2-javascript-4km9).

Now you can remove all those annoying `var self = this` lines as they are now completely unnecessary!

## Installation

```bash
npm install nothis
```

## Functions

- `decorator` - @context function decorator for Class functions.
- `nothis` - passes `this` as an argument.
- `fixthis` - Prevents the rebinding of `this`.
- `nothisAll` - Prevents the rebinding of `this` for React.

## nothis :: function -> function

### Example: Decorator

Basic JavaScript object

```javascript
import context from 'nothis/contextDecorator'

class Cat {
sound = 'meow'

@context
speak(ctx) {
return ctx.sound
}

@context
speak2 = ctx => ctx.sound
}

const cat = new Cat()

cat.speak() //=> 'meow'
cat.speak2() //=> 'meow'
```

### Example 1: Basics

Basic JavaScript object

```javascript
// 😞 GROSS: this
const cat = {
sound: 'meow',
speak: function() {
return this.sound
}
}

// 🔥 LIT: nothis
import nothis from 'nothis'

const cat = {
sound: 'meow',
speak: nothis(function(ctx) {
return ctx.sound
})
}
```

### Example 2: Arrow functions

Arrow functions with `this` won't work. But with `nothis` you can still access the context.

```javascript
// 😞 GROSS: this
const cat = {
sound: 'meow',
speak: () => this.sound
}
cat.speak()
//=> undefined

// 🔥 LIT: nothis
const cat = {
sound: 'meow',
speak: nothis(ctx => ctx.sound)
}
cat.speak()
//=> "meow"
```

### Example 3: Multiple arguments

```javascript
const cat = {
sound: 'meow',
speak: nothis((ctx, end) => ctx.sound + end)
}
cat.speak('!')
// => "meow!"
```

### Example 4: Clarity

Easily know what your context is.

```javascript
// 😞 GROSS: this
const cat = {
sound: 'meow',
speak: function() {
return this.sound
},
crazy: function() {
setInterval(function() {
console.log(this.speak())
}, 1000)
}
}
cat.speak()
//=> Error: this.speak is not a function

// 🔥 LIT: nothis
const cat = {
sound: 'meow',
speak: function() {
return this.sound
},
crazy: nothis(function(ctx) {
setInterval(function() {
console.log(ctx.speak())
}, 1000)
})
}
cat.crazy()
// => "meow"
// => "meow"
// => "meow"
```

### Example 5: 3rd Party Libraries

3rd party libraries sometimes require you to use `this`. F that.

```javascript
// 😞 GROSS: this
$('p').on('click', function() {
console.log($(this).text())
})

// 🔥 LIT: nothis
$('p').on('click', nothis(ctx => console.log($(ctx).text())))
```

You can also use parameter destructuring in ES6 arrow functions.

```javascript
import { EventEmitter2 } from 'eventemitter2'
const events = new EventEmitter2({ wildcard: true })

// 😞 GROSS: this
events.on('button.*', function() {
console.log('event:', this.event)
})

// 🔥 LIT: nothis + destructuring!
events.on('button.*', nothis(({ event }) => console.log('event', event)))

events.emit('button.click')
```

## fixthis :: object -> object

Sometimes `this` will get rebound to another context when you least expect it. Consider this example.

```javascript
// 😞 GROSS: this
const cat = {
sound: 'meow',
speak: function() {
return this.sound
}
}
const speak = cat.speak

speak()
// => undefined
```

You can prevent this from happening by using `fixthis`.

```javascript
// 🔥 LIT: fixthis
import fixthis from 'nothis/fixthis'

const cat = fixthis({
sound: 'meow',
speak: function() {
return this.sound
}
})
const speak = cat.speak

speak()
// => "meow"
```

### ES6 Classes

Classes won't save you from the problems of `this`.

```javascript
// 😞 GROSS: this
class Cat {
constructor() {
this.sound = 'meow'
}
speak() {
return this.sound
}
}

const cat = new Cat()
const speak = cat.speak
speak()
// => Cannot read property 'sound' of undefined
```

You still can `fixthis` it.

```javascript
// 🔥 LIT: fixthis
class Cat {
constructor() {
this.sound = 'meow'
}
speak() {
return this.sound
}
}

const cat = fixthis(new Cat())
const speak = cat.speak
speak()
//=> "meow"
```

## fixthisReact :: object -> void

Apply `fixthisReact` to your React component and never have to use `this` again!

```javascript
import React from 'react'
import nothisAll from 'nothis/nothisAll'

// 🔥 LIT: no this in sight!
class Counter extends React.Component {
state = { count: 0 }

constructor() {
super()
nothisAll(this)
}

increment({ setState }) {
setState(({ count }) => ({ count: count + 1 }))
}

render({ increment, state }) {
return (


{state.count}

)
}
}
```

![Tombstone - this 1995-2018](https://github.com/joelnet/nothis/raw/master/assets/headstone-212x250.png)