Add traits for exploiting SFINAE

CMakeLists.txt

@@ -28,6 +28,7 @@ set(HEADER_FILES
     math/math.h
     misc/memory.h
     misc/random.h
+    misc/traits.h
     tests/testutils.h
     tests/cppunit.h
 )

misc/traits.h

@@ -0,0 +1,39 @@
+#ifndef CPP_UTILITIES_TRAITS_H
+#define CPP_UTILITIES_TRAITS_H
+
+#include <type_traits>
+
+namespace Traits {
+
+namespace Detail {
+    enum class Enabler {};
+}
+
+template <typename If, typename Then, typename Else>
+using Conditional = typename std::conditional<If::value, Then, Else>::type;
+
+template <bool B, typename...>
+struct Bool : std::integral_constant<bool, B> {};
+
+template <typename T>
+using Not = Bool<!T::value>;
+
+template <typename... T>
+struct Any : Bool<false> {};
+
+template <typename... T>
+struct All : Bool<true> {};
+
+template <typename Head, typename... Tail>
+struct All<Head, Tail...> : Conditional<Head, All<Tail...>, Bool<false> > {};
+
+template <typename... Condition>
+using EnableIf = typename std::enable_if<All<Condition...>::value, Detail::Enabler>::type;
+
+template <typename... Condition>
+using DisableIf = typename std::enable_if<!All<Condition...>::value, Detail::Enabler>::type;
+
+}
+
+#endif // CPP_UTILITIES_TRAITS_H
+