Detect unreachable code

```js
const myFunction = (x) => {
  if(x>0){
    return "ok"
  } else {
    throw "not ok"
  }

  if(x>0){
    return "ok"
  } else {
    throw "not ok"
  }
}
```

The second if is unreachable so it will never be executed and it shouldn't be printed or be printed highlighting that it's unreachable.