yarn add @resinfo/async
# or
npm install --save @resinfo/async

module Async = Resinfo_async
// Construct from a promise
let fetch = url => {
  Async.fromPromise(
    // assume "get" is a previously defined promise function
    () => get(url),
    ~resolve=json => Ok(json),
    ~reject=_ => Error()
  )
}
// This is a regular value that can be passed around like
// any other; it isn't run until explicitly called
let fetchProfile = {
  fetch("https://api.github.com/users/resinfo")
  ->Async.map(result => {
    switch result {
      | Ok(json) => json.login
      | Error() => "Unable to get user"
    }
  })
}
// Run as callback
fetchProfile->Async.run(name => {
  Js.log2("Name is", name)
})
// Run as promise
fetchProfile
  ->Async.toPromise
  ->Js.Promise.then_(name => {
    Js.log2("Name is", name)
    Js.Promise.resolve()
  }, _)