Benchmark: timing 1000000 iterations of chars, charvar, i...
     chars:  2 wallclock secs ( 1.97 usr +  0.00 sys =  1.97 CPU) @ 507614.21/s (n=1000000)
   charvar:  3 wallclock secs ( 2.04 usr + -0.01 sys =  2.03 CPU) @ 492610.84/s (n=1000000)
         i:  1 wallclock secs ( 1.31 usr +  0.00 sys =  1.31 CPU) @ 763358.78/s (n=1000000)
            Rate charvar   chars       i
charvar 492611/s      --     -3%    -35%
chars   507614/s      3%      --    -34%
i       763359/s     55%     50%      --