async-iterator.mli

(*
  next(cb).
    - Calls cb(Error) if error
    - Calls cb(null, value) if value
    - Calls cb(null, undefined) if finished
    
  end(cb)
    - Aborts the underlying stream
    - calls cb() once cleaned up
    
  A stream is a ordered sequence of
  
    - zero or more Data followed by Error or Finished
*)
type AsyncIterator := {
  next: ((Error | null, Any | undefined) => void) => void,
  end: (() => void) => void
}