Benchmark: timing 100 iterations of SCHWARTZ, SUBSTR...
  SCHWARTZ:  1 wallclock secs ( 1.30 usr +  0.02 sys =  1.31 CPU) @ 76.16/s (n=100)
    SUBSTR:  2 wallclock secs ( 0.97 usr +  0.00 sys =  0.97 CPU) @ 103.31/s (n=100)