diff --git a/grammar_parser/list.inc b/grammar_parser/list.inc
index c14cbaf..3e5276b 100644
--- a/grammar_parser/list.inc
+++ b/grammar_parser/list.inc
@@ -2304,10 +2304,13 @@ class PGPString extends PGPExpression {
           break;
 
         case 'open':
-        case 'close':
           $string .= $data['value'];
           break;
 
+        case 'close':
+          $string .= $data;
+          break;
+
         case 'operand':
           $string .= $data->toString($indent);
           break;