hide

$group hide: hides group if constraint noprint, otherwise hides subsequent elements with constraint noprint
$group hide yes yes: hides group in any case
$group hide no: unveils group

obj method group hide {{yesNo yes} {noPrint no}} {
  if {$yesNo && [$self constraint noprint]} then {
    $self elements hide yes yes
  } else {
    $self elements hide $yesNo $noPrint
  }
}