I do have a copy of the second edition. At the top of page 255 Friedl says

Somewhat related, users of Perl that read the first edition of this book may sometimes write something like ^[Ff][Rr][Oo][Mm]: instead of a case-insensitive use of ^from:. Old versions of Perl were very ineffecient with their case-insensitive matching, so I recommended the use of classes like this in some cases. That recomendation has been lifted, as the case-insensitive inefficiency has been fixed for some years now.

I have not read the first edition of the book, so i don't know whether it's worthwhile to upgrade. I can say that Mastering Regular Expressions is one of the most useful and readable reference manuals I have ever seen. It has my highest recomentation.

-- Fuzzy Frog
My "highest recomendation" may not be much, but it's all I have to give.

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

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