Why does:
$string =~ s/\^s//g;
$string =~ s/\s$//g;
$string =~ s/\s+$//g;
run faster than:
$string =~ s/\^s|\s$|\s+$/g;
on long strings?
you would think that because the second one is using a short circuit operator it would be faster because it only has to read through the string once instead of three times, but it is not.

In reply to question about reg exp engine by chuckd

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