drabinowitz

  const maybePets: Array<Pet | undefined> = [...]
  const pets: Array<Pet> = maybePets.filter((v: Pet | undefined): v is Pet => v != undefined)

  function MyReactComponent() {
    const [
      [width, setWidth],
      [name, setName],
    ] = React.use(
      [useWidth],
      [useName, 'alice'],
    );
    return <div>{width} {name}</div>
  }