golang-promise

This is a small project detailing how to create a promise like structure in golang with sync.WaitGroups. I created it to streamline fetching several results from multiple sources async.

result := ""
myErr := new(error)
wg := new(sync.WaitGroup)
wg.Add(1)

NewPromise[string](func() (string, error) {
  str, err := doSomething()
  if err != nil {
    return nil, err
  }

  return str, nil
}).Then(func(str string) {
  result = str
}, func(e error) {
  myErr = e
}).Finally(func() {
  wg.Done()
})

if myErr != nil {
  handleError()
}

wg.Wait()