Benchmark: running regex, split, each for at least 100 CPU seconds...
     regex: 136 wallclock secs (110.38 usr +  0.32 sys = 110.70 CPU) @ 40548.93/s (n=4488766)
     split: 112 wallclock secs (100.00 usr +  0.02 sys = 100.02 CPU) @ 38995.86/s (n=3900366)