Sequential execution of Promises using generators and co()

promises_generators.js

function asyncFunc(e) {
  return new Promise((resolve, reject) => {
    setTimeout(() => resolve(e), e * 1000);
  });
}

const arr = [1, 2, 3];

co(function* () {
  let result = [];

  return arr.map(element => {
    return yield asyncFunc(element);
  })
}).catch(error => console.error(error));