BEGIN {
    use Regex::PreSuf;
    my %escape = ( "\n" => '\\n', "\t" => '\\t', "\\" => '\\\\');
    my $escape = presuf(keys %escape);
    my %unescape = reverse %escape;
    my $unescape = presuf(keys %unescape);

    sub escape {
        local $_ = shift;
        s/($escape)/$escape{$1}/go;
        $_;
    }

    sub unescape {
        local $_ = shift;
        s/($unescape)/$unescape{$1}/go;
        $_;
    }
}