Um, quotemeta? :D Do it in one pass like String::Escape
# $special_characters_escaped = backslash( $source_string );
sub backslash ($) {
    local $_ = ( defined $_[0] ? $_[0] : '' );
    # Preserve only printable ASCII characters other than \, ", $, and
+ @
    s/([^\x20\x21\x24\x25-\x39\x41-\x5b\x5d-\x7e])/\\$Backslashed{$1}/
+gs;
    return $_;
}

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In reply to Re: Faster way to regex this by Anonymous Monk
in thread Faster way to regex this by jar00n

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