Memo# - Regular Expressions - Part 2 - Substitutions with Grouping

Test String

7800000 (7.8M Characters)

"abbbcdexfbeczexczczkef111anncdehbzzdezf" * 200000

Very Simple Replace

regex pattern: bc , Replace with : TEST , mine is 2.5x faster

my regex sub 0.140000104904 s 8200000 abbTESTdexfbeczexczczkef111anncdehbzzdezfabbTESTdexfbeczexczczkef111anncde....

python's re sub 0.359999895096 s 8200000 abbTESTdexfbeczexczczkef111anncdehbzzdezfabbTESTdexfbeczexczczkef111anncde....

With Range Matching

regex pattern: [a-z]c , Replace with : TEST , mine is 6x faster

my regex sub 0.453000068665 s 9800000 abbTESTdexfbTESTzeTESTTESTzkef111anTESTdehbzzdezfabbTESTdexfbTESTze....

python's re sub 2.82800006866 s 9800000 abbTESTdexfbTESTzeTESTTESTzkef111anTESTdehbzzdezfabbTESTdexfbTESTze....

With Range Matching + Grouping

regex pattern: ([a-z])(c) , Replace with : AA\2\1BB , mine is 27x faster

my regex sub 0.641000032425 s 11800000 abbAAcbBBdexfbAAceBBzeAAcxBBAAczBBzkef111anAAcnBBdehbzzdezfabbAAcbBB....

python's re sub 17.7969999313 s 11800000 abbAAcbBBdexfbAAceBBzeAAcxBBAAczBBzkef111anAAcnBBdehbzzdezfabbAAcbBB....

Cheers,
Mark