1 files changed, 5 insertions, 0 deletions
diff --git a/asl/meta.hpp b/asl/meta.hpp
index d05b095..d253dda 100644
--- a/asl/meta.hpp
+++ b/asl/meta.hpp
@@ -67,6 +67,9 @@ template<typename T> concept trivially_destructible = __is_trivially_destructibl
 
 template<typename T> concept trivially_copyable = __is_trivially_copyable(T);
 
+template<typename From, typename To>
+concept convertible = __is_convertible(From, To);
+
 using nullptr_t = decltype(nullptr);
 
 template<typename T> struct _un_const_helper          { using type = T; };
@@ -81,6 +84,8 @@ template<typename T> using un_volatile_t = _un_volatile_helper<T>::type;
 
 template<typename T> using un_cv_t = un_volatile_t<un_const_t<T>>;
 
+template<typename T> using un_cvref_t = un_ref_t<un_cv_t<T>>;
+
 template<typename T> concept is_void = is_same<void, un_cv_t<T>>;
 
 template<typename T> struct _is_ref_helper      { static constexpr bool l = false; static constexpr bool r = false; };