Hi davido
well it was in June, below what I found on my disk:
There is an "X" in the middle of a 52MB string of repeated alphabet letters ($pattern = join "","a".."z")
Depending if you look for "Xabc..xyz" or "abc...xyzX" the different approaches show their strength.
I did more tests which I can't find anymore strongly indicating that index doesn't use Boyer-Moore.
Just vary the position of the "X".
I'd be glad if you looked it over. :)
use Time::HiRes qw[ time ];
my $pattern = join "","a".."z";
my $str= $pattern x 1E6 . "X" .$pattern x1E6;
$\="\n";
$|=1;
print "Length: ",length $str;
print "\n---End X";
$start=time;
print "Match: ", $str =~/${pattern}X/;
printf "\t took %.3f sec\n",time-$start;
$start=time;
print "Index: ", index $str , "${pattern}X";
printf "\t took %.3f sec\n",time-$start;
print "\n---Start X";
$start=time;
print "Match: ", $str =~/X${pattern}/;
printf "\t took %.3f sec\n",time-$start;
$start=time;
print "Index: ", index $str , "X${pattern}";
printf "\t took %.3f sec\n",time-$start;
RESULT:
Length: 52000001
---End X
Match: 1
took 0.021 sec
Index: 25999974
took 0.263 sec
---Start X
Match: 1
took 0.165 sec
Index: 26000000
took 0.094 sec
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