Getting an error using the base example. about react-native-threads HOT 1 CLOSED

import { self } from 'react-native-threads';

// listen for messages
self.onmessage = (message) => {
  console.log(message);
}

// send a message, strings only
self.postMessage('hello');

const thread = new Thread('threadfile.js');

// send a message, strings only
thread.postMessage('hello');

// listen for messages
thread.onmessage = (message) => console.log(message);

// stop the JS process
thread.terminate();