Benchmark: timing 100000 iterations of index, re...
     index:  4 wallclock secs ( 3.54 usr +  0.00 sys =  3.54 CPU) @ 28248.59/s (n=100000)
        re:  7 wallclock secs ( 6.98 usr +  0.00 sys =  6.98 CPU) @ 14326.65/s (n=100000)