my $actions = "1)blah\n...2)blah\n...3)blah\n...4)\blah\n";
my $response = $mw->messageBox( -title => $STD_TITLE,
       -message => "HEY!! This will do:\n $actions\n\n".
                   "DO YOU WANT TO PROCEED?\n\n", 
       -type => 'YesNoCancel');
print "yes clicked" if ($response =~/^Yes$/i); #of course you do it, not print