# TS1433: Neither decorators nor modifiers may be applied to 'this' parameters.

> A decorator or a modifier such as `public` is applied to a `this` parameter. Remove it.

## What it means

A `this` parameter only declares the type of `this` inside a function. It isn't a real
parameter, so it can't have decorators or modifiers like `public` or `readonly`.

## Example

```ts
declare function track(...args: unknown[]): void;

export class Counter {
  count = 0;
  increment(@track this: Counter) {
    this.count++;
  }
}
```

## How to fix

- Remove the modifier or decorator from `this`.

Source: https://ts-r.dev/errors/TS1433/