Promise Pattern: Loop helper function to sequentially loop through an array of promises

promise-patterns-loop.js

console.clear();

const loop = (arrayOfPromises, guard) => {
  if (arrayOfPromises.length && (!guard || guard(arrayOfPromises[0]))) {
    return arrayOfPromises.shift()().then(() => {
      return loop(arrayOfPromises, guard);
    })
  }
  
  return Promise.resolve();
}

const longOp = () => new Promise((resolve, reject) => {
  console.log('longOp');
  setTimeout(resolve, 200);
});

const ops = Array.from(Array(10)).map(() => longOp);

loop(ops)
  .then(() => console.log('done'))
  .catch(() => console.log('whooops'))
  .finally(() => console.log('finally'))
  ;