1 files changed, 68 insertions, 0 deletions
diff --git a/modules/codec/c++/schema_meta.hpp b/modules/codec/c++/schema_meta.hpp
new file mode 100644
index 0000000..a37197a
--- /dev/null
+++ b/modules/codec/c++/schema_meta.hpp
@@ -0,0 +1,68 @@
+#pragma once
+
+#include "schema.hpp"
+
+namespace saw {
+
+template<typename Schema>
+struct meta_schema {
+	static_assert(always_false<Schema>, "Not supported Schema.");
+};
+
+template<>
+struct meta_schema<schema::Void> {
+	using Schema = schema::Void;
+	using MetaSchema = schema::Void;
+};
+
+template<typename T, uint64_t N>
+struct meta_schema<schema::Primitive<T,N>> {
+	using MetaSchema = schema::Void;
+	using Schema = schema::Primitive<T,N>;
+};
+
+template<typename TA, uint64_t NA, typename TB, uint64_t NB> 
+struct meta_schema<schema::MixedPrecision<schema::Primitive<TA,NA>, schema::Primitive<TB,NB> >> {
+	using Schema = schema::MixedPrecision<schema::Primitive<TA,NA>, schema::Primitive<TB,NB>>;
+	using MetaSchema = schema::Void;
+};
+
+template<typename... T, string_literal... Lit>
+struct meta_schema<schema::Struct<schema::Member<T,Lit>...>> {
+	using MetaSchema = schema::Struct<schema::Member<typename meta_schema<T>::MetaSchema,Lit>...>;
+	using Schema = schema::Struct<schema::Member<T,Lit>...>;
+};
+
+template<typename... T, string_literal... Lit>
+struct meta_schema<schema::Union<schema::Member<T,Lit>...>> {
+	using MetaSchema = schema::Union<schema::Member<typename meta_schema<T>::MetaSchema,Lit>...>;
+	using Schema = schema::Union<schema::Member<T,Lit>...>;
+};
+
+template<typename... T>
+struct meta_schema<schema::Tuple<T...>> {
+	using MetaSchema = schema::Tuple<typename meta_schema<T>::MetaSchema...>;
+	using Schema = schema::Tuple<T...>;
+};
+
+template<>
+struct meta_schema<schema::String> {
+	using MetaSchema = schema::UInt64;
+	using Schema = schema::String;
+};
+
+/**
+ * Technically we also can distinguish if T is primitive.
+ */
+template<typename T, uint64_t Dim>
+struct meta_schema<schema::Array<T,Dim>> {
+	using MetaSchema = schema::FixedArray<schema::UInt64,Dim>;
+	using Schema = schema::Array<T,Dim>;
+};
+
+template<typename T, uint64_t Dim>
+struct meta_schema<schema::FixedArray<T,Dim>> {
+	using MetaSchema = schema::Void;
+	using Schema = schema::FixedArray<T,Dim>;
+};
+}