code: func (pack *Package) MultiAck() (err error) {
  	if pack.Collection == nil {
  		return fmt.Errorf("cannot MultiAck single package")
  	}
  	// TODO write in lua
  	for i := 0; i <= pack.index(); i++ {
  		var p *Package
  		p = (*pack.Collection)[i]
  		// if the package has already been acked just skip
  		if p.Acked == true {
  			continue
  		}
  
  		err = pack.Consumer.ackPackage(p)
  		if err != nil {
  			break
  		}
  		p.Acked = true
  	}
  	return
  }
docs: // MultiAck removes all packaes from the fetched array up to and including this package