or download this
# within
while (my $x = $count) {
...
Benchmark: timing 10 iterations of within, without...
within: 40 wallclock secs (39.78 usr + 0.04 sys = 39.82 CPU) @ 0
+.25/s (n=10)
without: 35 wallclock secs (35.09 usr + 0.00 sys = 35.09 CPU) @ 0
+.28/s (n=10)