Benchmark: timing 1000000 iterations of count, slice...
     count:  2 wallclock secs ( 3.18 usr +  0.01 sys =  3.19 CPU) @ 313479.62/s (n=1000000)
     slice:  3 wallclock secs ( 3.04 usr +  0.06 sys =  3.10 CPU) @ 322580.65/s (n=1000000)