That's a great question, and until you asked it, I hadn't even caught that. (I had just copy/pasted the error straight from the log, and noticed it was focused on that regex section.)

The code did not contain a double backslash. I copied that line exactly as you had posted it, and it was and still is as follows in the code:

foreach my $line (@data) {
    push @changed, $line =~ s{$s$c$b\K$m(?=$b$c$e)}{$regexR}r;
}

[download]

I haven't used the //r before. That is new to me. What does it do? I wondered if it might be the syntax error.

Blessings,

~Polyglot~

In reply to Re^4: Executing CGI/web form directives in regex substitution without pages of code by Polyglot
in thread Executing CGI/web form directives in regex substitution without pages of code by Polyglot

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