A code example from the article https://www.joshwulf.com/blog/2020/03/array-async-failure

async-reducer-machine.js

// Takes an array of async tasks that may throw of shape {run: () => Promise<result>}
// Returns Promise<{error: error[], success: result[]}>

async function executeAsyncTasks(arrayOfAsyncTasks) {
  const success = async res => ({ success: await res }) // Promise<{success: res}>
  const error = async err => ({ error: await err }) // Promise<{error: e}>

  const runWithResult = task => task.run().then(success).catch(error)
  const outcomes = await Promise.all(arrayOfAsyncTasks.map(runWithResult))

  const outcomesFlat = outcomes.reduce((acc, o) => o.error ? 
    { error: [...acc.error, o.error], success: acc.success } :
    { error: acc.error, success: [...acc.success, o.success] }, 
    { error: [], success: [] })
  return outcomesFlat
}