+sub merge_package_lists($$) {
+ my $list1 = shift;
+ my $list2 = shift;
+ my @l = ();
+ my %pkgs;
+
+ foreach my $pkg (@$list1, @$list2) {
+ $pkgs{$pkg} = 1;
+ }
+ foreach my $pkg (keys %pkgs) {
+ push @l, $pkg unless ($pkg =~ /^-/ or $pkgs{"-$pkg"});
+ }
+ return sort(@l);
+}