# Disallow aliasing `this` (no-this-alias)

This rule prohibts assigning variables to `this`.

## Rule Details

Rationale from TSLint:

> Assigning a variable to `this` instead of properly using arrow lambdas may be a symptom of pre-ES6 practices
> or not managing scope well.
>
> Instead of storing a reference to `this` and using it inside a `function () {`:
>
> ```js
> const self = this;
>
> setTimeout(function() {
>   self.doWork();
> });
> ```
>
> Use `() =>` arrow lambdas, as they preserve `this` scope for you:
>
> ```js
> setTimeout(() => {
>   this.doWork();
> });
> ```

Examples of **incorrect** code for this rule:

(see the rationale above)

Examples of **correct** code for this rule:

(see the rationale above)

### Options

You can pass an object option:

```json5
{
  '@typescript-eslint/no-this-alias': [
    'error',
    {
      allowDestructuring: true, // Allow `const { props, state } = this`; false by default
      allowedNames: ['self'], // Allow `const self = this`; `[]` by default
    },
  ],
}
```

## When Not To Use It

If you need to assign `this` to variables, you shouldn’t use this rule.

## Related to

- TSLint: [`no-this-assignment`](https://palantir.github.io/tslint/rules/no-this-assignment/)