reffactored and recurrent implementation

include/NeuralNetwork/Stringifiable.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <sstream>
+
+namespace NeuralNetwork {
+	class Stringifiable {
+		public:
+
+			virtual ~Stringifiable() {
+			}
+
+			/**
+			 * @brief This is a virtual function for class
+			 */
+			virtual void stringify(std::ostream& out) const =0;
+
+			virtual std::string stringify() final {
+				std::ostringstream s;
+				stringify(s);
+				return s.str();
+			}
+
+	};
+
+	static std::ostream& operator<<(std::ostream& o, const Stringifiable& n) {
+		n.stringify(o);
+		return o;
+	}
+}