While I am impressed with everyone's research into the relative performance between m/foo/i and m/[fF][oO][oO]/ , Isn't it most important to keep your code readable and maintainable? Unless you are experiencing a specific performance problem, I wouldn't worry too much over it. And if you ARE experiencing a performance problem, I would make sure that the comments were properly verbose:

# This was changed in the interest of performance, the 
# regex are equivilent in function
# /new/i 
/[nN][eE][wW]/

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I'm generally against sacrificing maintainablilty for performance without strong justification, but there are of course those who disagree (and in many situations, they're right)

In reply to Re: Did the inefficiency of /i get fixed? by benrwebb
in thread Did the inefficiency of /i get fixed? by Cody Pendant

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