const fs = require('fs');

fs.writeFile('example.txt', 'Hello World', (err) => {
  if (err) throw err;
  fs.readFile('example.txt', 'utf8', (err, data) => {
    if (err) throw err;
    console.log(data);
  });
});

// file1.js
export const data = 'Hello';

// file2.js
import { data } from './file1.js';
console.log(data);

// file1.js
export const data = 'Hello';

// file2.js
import { data } from './file1.js';
console.log(data);