A solution by TypeScript of this this problem

```ts
class X {
f = 1
fn(this: X) {
// ~~~~~~~ have to write this
console.log(this.f)
}
}
const x = new X

setTimeout(x.fn, 2000) // No type error but runtime bug
safeTimeout(x.fn, 2000)
// Argument of type '(this: X) => void' is not assignable to parameter of type '(this: void) => {}'.
// The 'this' types of each signature are incompatible.
// Type 'void' is not assignable to type 'X'.(2345)

function safeTimeout(
f: (this: void, ...args: T) => {}, time: number, ...args: T
) {
return setTimeout(f, time, ...args)
}
```