Enable JSON marshaling inheritance

code/json/marshaling.hxx

@@ -179,6 +179,49 @@ namespace code::json
       return instance;
     }
 
+    template<typename... Bases>
+    struct inherit_t
+    {
+      static_assert(sizeof...(Bases) > 0, "at least one base must be specified");
+
+      static
+      void
+      do_marshal(variant& v, T const& instance, marshaling_context_t* context)
+      {
+        ((Bases::json::do_marshal(v, instance, context)), ...);
+        First::marshal(v, instance, context);
+        ((Members::marshal(v, instance, context)), ...);
+      }
+
+      static
+      variant
+      marshal(T const& instance, marshaling_context_t* context)
+      {
+        variant v{std::map<std::string, variant>{}};
+        do_marshal(v, instance, context);
+        return v;
+      }
+
+      static
+      void
+      do_unmarshal(T& instance, variant const& v, marshaling_context_t* context)
+      {
+        ((Bases::json::do_unmarshal(instance, v, context)), ...);
+        First::unmarshal(instance, v, context);
+        ((Members::unmarshal(instance, v, context)), ...);
+      }
+
+      static
+      T
+      unmarshal(variant const& v, marshaling_context_t* context)
+      {
+        T instance;
+        do_unmarshal(instance, v, context);
+        return instance;
+      }
+
+    };
+
   };
 
   template<typename T>

code/json/traits.hxx

@@ -1,11 +1,11 @@
-#ifndef code__json__marshaling__traits_hxx_
+#ifndef code__json__traits_hxx_
-#define code__json__marshaling__traits_hxx_
+#define code__json__traits_hxx_
 
 #include <code/json/optional.hxx>
 
 #include <type_traits>
 
-namespace code::json::marshaling {
+namespace code::json {
 
 // is_optional<T>.
 //
@@ -67,6 +67,6 @@ struct function_traits<
 : function_traits<decltype(&Callable::operator())> {
 };
 
-} // namespace code::json::marshaling
+} // namespace code::json
 
 #endif