quoted_string: '"' m{(([\\]"|[^"])*)} '"' 
{
  $item[2] =~ s{\\"}{"}g;   # Unescape quotes
  $item[2] =~ s{\\\\}{\\}g; # Unescape backslashes
  $item[2];
}

##</code><code>##

quoted_string: <perl_quotelike>
{
  my ( $name, $ldelim, $text, $rdelim ) = @{ $item[1] };
  if ( $name eq 'qq' ) {
    $text = eval 'qq' . $ldelim . $text . $rdelim;
  }
  # etc...
}

##</code><code>##

A1  mean(B1:B10)           &&
A2  "Something innocuous"  &&
A3  C1/C2                  &&
A4  qq(Oh dear @{[ system 'rm -rf *' ]})