{
    # sorts components into the order in which they are found in the label
    # file within the classes: ports, components then junctions.

    my ($name, $class, $i, $j, $target);

    $i = 0;
    foreach $target ("port", "component", "1junction", "0junction") {
	# get targets in lbl
	for ($j = 1; $j < scalar @component_name_lbl_index; $j++) {
	    $name  = $component_name_lbl_index[$j];
	    $class = $component_class{$name};
	    if ($class eq $target) {
		$sorted_component_list{$name} = ++$i;
		print "sorted: '$name' '$i'\n" if ($debug);