$temp =~ s/#$'//; I'm not even sure what you want that to do, but it constructs a regex out of # followed by whatever was followed by the previous match. Any regex special characters in that generated string will be interpreted as regex directives.

You probably want something like: 

while (chomp(my $temp=<INPUT>)){
    print Dumper $temp;
    $temp =~ s/#.*//;  # remove comments
    if ($temp =~ /^\s*$/){
        next;
    }
    print "after regex:\n";
    print Dumper $temp;
    print "end\n";
}

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In reply to Re: Regex error when [] occurs in file.. by Joost
in thread Regex error when [] occurs in file.. by why_bird

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