diff --git a/Meta/tuple_cat.h b/Meta/tuple_cat.h
new file mode 100644
index 0000000..79f7079
--- /dev/null
+++ b/Meta/tuple_cat.h
@@ -0,0 +1,24 @@
+static_assert( __cplusplus > 2020'99 );
+
+#pragma once
+
+#include <Alepha/Alepha.h>
+
+#include <tuple>
+
+#include <Alepha/type_lisp.h>
+
+namespace Alepha::Hydrogen::Meta  ::detail::  tuple_cat_m
+{
+	inline namespace exports
+	{
+		template< typename Left, typename Right >
+		using tuple_cat_t= tuple_from_list_t< list_cat_t< list_from_tuple_t< Left >, list_from_tuple_t< Right > > >;
+	}
+}
+
+namespace Alepha::Hydrogen::Meta::inline exports::inline tuple_cat_m
+{
+	using namespace detail::tuple_cat_m::exports;
+}
+
diff --git a/type_lisp.h b/type_lisp.h
index ca2331f..b8e36bd 100644
--- a/type_lisp.h
+++ b/type_lisp.h
@@ -141,6 +141,27 @@ namespace Alepha::Hydrogen  ::detail::  type_lisp_m
 	{
 		using type= TypeList< LeftArgs..., RightArgs... >;
 	};
+
+	template< typename Item, std::size_t count >
+	struct repeat;
+
+	namespace exports
+	{
+		template< typename Item, std::size_t count >
+		using repeat_t= typename repeat< Item, count >::type;
+	}
+
+	template< typename Item, std::size_t count >
+	struct repeat
+	{
+		using type= cons_t< Item, repeat_t< Item, count - 1 > >;
+	};
+
+	template< typename Item >
+	struct repeat< Item, 0 >
+	{
+		using type= Nil;
+	};
 }
 
 namespace Alepha::Hydrogen::inline exports::inline type_lisp_m