Benchmark: timing 100000 iterations of join, loop, quote...
      join:  3 wallclock secs ( 2.30 usr +  0.00 sys =  2.30 CPU) @ 43402.78/s (n=100000)
      loop: 17 wallclock secs (16.03 usr +  0.00 sys = 16.03 CPU) @ 6237.52/s (n=100000)
     quote:  5 wallclock secs ( 3.79 usr +  0.00 sys =  3.79 CPU) @ 26420.08/s (n=100000)