code: func emailsForReg(id int, dbMap dbSelector) ([]string, error) {
  	var contact contactJSON
  	err := dbMap.SelectOne(&contact,
  		`SELECT id, contact
  		FROM registrations
  		WHERE contact != 'null' AND id = :id;`,
  		map[string]interface{}{
  			"id": id,
  		})
  	if err == sql.ErrNoRows {
  		return []string{}, nil
  	}
  	if err != nil {
  		return nil, err
  	}
  
  	var contactFields []string
  	var addresses []string
  	err = json.Unmarshal(contact.Contact, &contactFields)
  	if err != nil {
  		return nil, err
  	}
  	for _, entry := range contactFields {
  		if strings.HasPrefix(entry, "mailto:") {
  			addresses = append(addresses, strings.TrimPrefix(entry, "mailto:"))
  		}
  	}
  	return addresses, nil
  }
docs: // Finds the email addresses associated with a reg ID