generatorの並列実行と直列実行

paralle.js

const co = require('co');

// 0‾1秒の処理
const proc = function*() {
  const wait = Math.random();
  return new Promise(resolve =>
    setTimeout(function() {
      return resolve(wait);
    }, wait * 1000)
  );
};

co(function*() {
  //並列実行
  console.time('parallel');
  const parallel = yield Array.from({ length: 10 }).map(() => {
    return proc();
  });
  console.timeEnd('parallel');
  console.log(parallel);

  //直列実行
  console.time('serial');
  const serial = [];
  for (let i = 0; i < 10; i++) {
    serial.push(yield proc());
  }
  console.timeEnd('serial');
  console.log(serial);
})
  .catch(err => {
    console.error(err);
  });