my $CHECK; BEGIN { my ( @DBs, $mod); $CHECK = 0; @DBs = qw(XML::TreeBuilder); for $mod (@DBs) { if ( eval "require $mod") { $mod-> import (); #if needed $CHECK = 1; last; } } if ( $CHECK ) { $CHECK = "XML::TreeBuilder"; } #"None of @DBs loaded" unless $found; }