I was going to answer something like that, but forgot all about it. In the meantime, I've read (once again) some parts of CGI.pm, and found these interesting regexes:

         $toencode =~ s{&}{&}gso;
         $toencode =~ s{<}{&lt;}gso;
         $toencode =~ s{>}{&gt;}gso;
         $toencode =~ s{"}{&quot;}gso;
...
                $toencode =~ s{'}{&#39;}gso;
                $toencode =~ s{\x8b}{&#139;}gso;
                $toencode =~ s{\x9b}{&#155;}gso;
...
                     $toencode =~ s{\012}{&#10;}gso;
                     $toencode =~ s{\015}{&#13;}gso;

[download]

That's at least 9 uses of /o with no variable interpolation in the pattern.

But CGI also doesn't use strict, has no spaces after commas, uses C-style for-loops where lists where more efficient and better readable, assumes that the IP address "0" equals "127.0.0.1", has ugly #-laden comments, etc... So is the use of /o really more efficient when no variable interpolation is used, or is this yet another strange thing in CGI.pm. (Excuse me for being so negative about CGI.pm, but having read it, I prefer my own set of functions even more.) 

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7220756E7061636B3F202F6D736720
6D6521203A29202D2D204A75657264

In reply to Re: Re: Re: •Re: Find illegal ASCII characters by Juerd
in thread Find illegal ASCII characters by fmogavero

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