# consistent-this

> Enforce one name for variables that hold `this`

Code that saves `this` for a nested function calls the variable `that`, `self`, `me` or `vm`. If you use one name everywhere, you know what the variable holds without looking up its declaration.

The rule reports `this` assigned to any other name. It also reports the chosen name when it holds something other than `this`. The default name is `that`.

{/* Generated by src/codegen/lint-rule-docs.ts. Do not edit this section. */}

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"consistent-this" = "error" # or "warn"
```

Every option, set to its default:

```toml bunfig.toml
[lint.rules]
"consistent-this" = ["error", "that"]
```

{/* End of the generated section. */}

## Examples

Reported:

{/* bad */}
```js
function Timer() {
  const self = this;
  setInterval(function () {
    self.tick();
  }, 1000);
}
```

{/* bad */}
```js
const that = document.body;
```

Not reported:

{/* good */}
```js
function Timer() {
  const that = this;
  setInterval(function () {
    that.tick();
  }, 1000);
}
```

Destructuring isn't an alias, so it's allowed:

{/* good */}
```js
function Timer() {
  const { interval, tick } = this;
  setInterval(tick, interval);
}
```

## Options

The options are one or more names you allow:

```toml bunfig.toml
[lint.rules]
consistent-this = ["error", "self", "vm"]
```

{/* good {"options": ["self", "vm"]} */}
```js
function Timer() {
  const self = this;
  setInterval(function () {
    self.tick();
  }, 1000);
}
```

## When not to use it

An arrow function uses the surrounding code's `this`, so new code rarely needs an alias at all.