sub get_proparg {
  my $propstr = shift;                     # get the property string
  my $level   = shift || return $propstr;  # get the level we want to extract
  my $cnt;                                 # initialize counter

  if($level == -1) {           # special case, get the innermost argument
    $propstr =~ /\(([^\(\)]+)\)+/;
    return $1;
  } else {                     # get whatever argument $level indicates
    for($cnt = 0;$cnt<$level; $cnt++) {
      $propstr =~ /\((.+)\)/;
      $propstr = $1;
    }
    return $propstr;
  }
}