diff --git a/src/parser/grammatical.y b/src/parser/grammatical.y
index e9cc152..0c933bf 100644
--- a/src/parser/grammatical.y
+++ b/src/parser/grammatical.y
@@ -65,7 +65,7 @@ inline void conferror(YYLTYPE *locp, yyscan_t sc, const char * str)
 %type <ob> pair
 %type <ob> list
 
-%destructor {} REAL INTEGER BOOL STRING
+%destructor {} REAL INTEGER BOOL
 %destructor {delete $$;} <*>
 
 %%