Benchmark: running inlineArrayLookup, preBuiltArrayLookup, strftimeLookup, substrLookup, each for at least 2 CPU seconds...
inlineArrayLookup:  2 wallclock secs ( 2.12 usr + -0.01 sys =  2.11 CPU) @ 543540.28/s (n=1146870)
preBuiltArrayLookup:  1 wallclock secs ( 2.04 usr + -0.01 sys =  2.03 CPU) @ 588310.34/s (n=1194270)
strftimeLookup:  3 wallclock secs ( 1.76 usr +  0.37 sys =  2.13 CPU) @ 216666.20/s (n=461499)
substrLookup:  2 wallclock secs ( 2.09 usr +  0.00 sys =  2.09 CPU) @ 465374.16/s (n=972632)
                        Rate strftimeLookup substrLookup inlineArrayLookup preBuiltArrayLookup
strftimeLookup      216666/s             --         -53%              -60%                -63%
substrLookup        465374/s           115%           --              -14%                -21%
inlineArrayLookup   543540/s           151%          17%                --                 -8%
preBuiltArrayLookup 588310/s           172%          26%                8%                  --