accout for cv in not_void

Author: TheNumbat

rpp/utility.h

@@ -9,16 +9,6 @@ namespace rpp {
 
 namespace detail {
 
-template<typename T>
-struct Is_Void {
-    constexpr static bool value = false;
-};
-
-template<>
-struct Is_Void<void> {
-    constexpr static bool value = true;
-};
-
 template<typename T>
 struct Is_Int {
     constexpr static bool value = false;
@@ -149,6 +139,26 @@ struct Remove_Const<const T> {
     using type = T;
 };
 
+template<typename T>
+struct Is_Volatile {
+    constexpr static bool value = false;
+};
+
+template<typename T>
+struct Is_Volatile<volatile T> {
+    constexpr static bool value = true;
+};
+
+template<typename T>
+struct Remove_Volatile {
+    using type = T;
+};
+
+template<typename T>
+struct Remove_Volatile<volatile T> {
+    using type = T;
+};
+
 template<typename T>
 struct Is_Pointer {
     constexpr static bool value = false;
@@ -234,6 +244,11 @@ struct Decay<const T> {
     using type = typename Decay<T>::type;
 };
 
+template<typename T>
+struct Decay<volatile T> {
+    using type = typename Decay<T>::type;
+};
+
 template<typename T>
 struct Decay<T&> {
     using type = typename Decay<T>::type;
@@ -433,10 +448,10 @@ template<typename T>
 concept Float = detail::Is_Float<T>::value;
 
 template<typename T>
-concept Not_Void = !detail::Is_Void<T>::value;
+concept Const = detail::Is_Const<T>::value;
 
 template<typename T>
-concept Const = detail::Is_Const<T>::value;
+concept Volatile = detail::Is_Volatile<T>::value;
 
 template<typename T>
 concept Pointer = detail::Is_Pointer<T>::value;
@@ -450,6 +465,9 @@ concept Lvalue_Reference = detail::Is_Lvalue_Reference<T>::value;
 template<typename T>
 concept Rvalue_Reference = detail::Is_Rvalue_Reference<T>::value;
 
+template<typename T>
+concept Not_Void = !detail::Is_Same<typename detail::Decay<T>::type, void>::value;
+
 template<typename T>
 concept Not_Function = detail::Is_Const<const T>::value || detail::Is_Reference<T>::value;
 
@@ -570,6 +588,9 @@ using With_Rvalue_Ref = T&&;
 template<typename T>
 using Without_Const = typename detail::Remove_Const<T>::type;
 
+template<typename T>
+using Without_Volatile = typename detail::Remove_Volatile<T>::type;
+
 template<typename T = void>
 struct Empty {};