$WARN = 0; #supress flow control warning in following block due to exiting anon sub
LOOPCTRL: while ($lb < 10){
    $exp->expect(...
        [ ..., sub {...
            $lb++;
            next LOOPCTRL; }],
        ...
    );
    $exp->expect(...
        [ ..., sub {...
            last LOOPCTRL; }]
    );
}
$WARN = 1; # reset to default