wip

pglablib/sqlast/Node.h

@@ -1,12 +1,25 @@
 #pragma once
 
+#include <QString>
+#include <stdexcept>
+#include <typeinfo>
+
 namespace sqlast {
 
+    class NodeVisitor;
+
     class Node {
     public:
         Node();
         virtual ~Node() = default;
 
+        virtual void Accept(NodeVisitor &visitor) = 0;
+        /// Every derived class that has child nodes should override these
+        /// to facilitate
+//        virtual int ChildCount() const { return 0; }
+//        virtual const Node* GetChild(int index) const { throw std::out_of_range("GetChild"); }
+
+        virtual QString ToString() const;
     };
 
 }