set_label(
   $frame_kontakte_haupt,
   $use_name,
   $use_name
   ? (
       { -text => "Nachname:" },
       {
           -textvariable => \$ref_hash_haupt->{nachname},
           -state        => '$ref_hash_berechtigung->{nachname}'
       }
     )
   : ()
);