C#'s using in JS, ish

using.js

const fs = require('fs');
const {promisify} = require('util');
const open = promisify(fs.open.bind(fs));

async function using(closable, fn) {
  const fd = await closable;
  try {
    await fn(fd);
  } finally {
    closable && typeof closable.close === "function" && closable.close();
  }
}

using(open("./file.js", "r+"), (fd) => new Promise(resolve => {
  const buffer = new Buffer(1024);
  fs.read(fd, buffer, 0, 1024, 0, (_, bytesRead, buffer) => {
    console.log("bytes read: ", bytesRead);
    console.log("bytes: " + buffer.toString());
    resolve();
  });
}));