Benchmark: running regex, split, each for at least 10 CPU seconds...
     regex: 12 wallclock secs (10.64 usr +  0.00 sys = 10.64 CPU) @ 40522.18/s (n=431156)
     split: 10 wallclock secs (10.02 usr +  0.00 sys = 10.02 CPU) @ 37290.82/s (n=373654)