sub make_max_finder {
        my $max;
        sub {
            for (@_) { $max = $_ if !defined $max || $_ > $max }
            $max;
        }
    }

##</code><code>##

    make_max_finder->(1..10); # 10

##</code><code>##

    my $max_finder = make_max_finder();
    $max_finder->($_) while <>;
    $max_finder->();  # retrieve maximum