add hierarchical node

include/links/NotImplementedLink.h

@@ -0,0 +1,24 @@
+#pragma once
+#include <vector>
+
+#include "ifaces/ILink.h"
+#include "Logger.h"
+
+template <class TElem>
+class NotImplementedLink : public ILink<TElem> {
+	using ElemPtr = std::shared_ptr<TElem>>;
+public:
+	NotImplementedLink(ElemPtr node) {}
+	ElemPtr getNode() const override { return nullptr; }
+	ElemPtr getParent() const override { return nullptr; }
+	void setParent(const ElemPtr& parent) override { }
+	const std::vector<ElemPtr>& getChildren() const override { return empty_; }
+	void addChild(const ElemPtr& child) override { }
+	void removeChild(const ElemPtr& child) override { }
+
+	~NotImplementedLink() override {
+		Logger::get("Link").dbg("--- Destructor called for: NotImplementedLink");
+	}
+private:
+	std::vector<ElemPtr> empty_;
+};