This came up from a discussion on what is faster, \d or [0-9],
Name "main::x" used only once: possible typo at digits.pl line 4. Benchmark: running classx, rangex, each for at least 10 CPU seconds... classx: 10 wallclock secs (10.00 usr + 0.00 sys = 10.00 CPU) @ 1034.90/s (n=10349) rangex: 10 wallclock secs (10.02 usr + 0.00 sys = 10.02 CPU) @ 327.84/s (n=3285)