Does this happen with real data? The reason 
my $test = 'illegal\\\\characters*example?';
my @illegal = qw(\ * ?);
my @legal = qw(bs a q);
my $c = 0;
foreach my $val (@illegal) {
    $test =~ s/\Q$val\E/[$legal[$c]]/g;
    $c++;
}
print $test."\n";

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returns illegal[bs]characters[a]example[q] is because the two \s are actually \ as an escape and then as the escaped character. From Quote and Quote like Operators: 
           A single-quoted, literal string.  A backslash
           represents a backslash unless followed by the
           delimiter or another backslash, in which case the
           delimiter or backslash is interpolated.

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To have two \s in your '-delimited string use '\\\\' (two escaped backslaches)
my $test = 'illegal\\\\characters*example?';
my @illegal = qw(\ * ?);
my @legal = qw(bs a q);
my $c = 0;
foreach my $val (@illegal) {
    $test =~ s/\Q$val\E/[$legal[$c]]/g;
    $c++;
}
print $test."\n";

[download]
If you are building up your string from component parts, it shouldn't be a concern.

In reply to Re: Disable Regex by james2vegas
in thread Disable Regex by SavannahLion

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