Benchmark: timing 10000 iterations of idiomatic, map...
 idiomatic:  1 wallclock secs ( 1.01 usr +  0.00 sys =  1.01 CPU) @ 9861.93/s (n=10000)
       map:  2 wallclock secs ( 2.08 usr +  0.00 sys =  2.08 CPU) @ 4819.28/s (n=10000)