Remove custom implementation for enum hashing

fairmq/Transports.h

@@ -9,7 +9,6 @@
 #ifndef FAIR_MQ_TRANSPORTS_H
 #define FAIR_MQ_TRANSPORTS_H
 
-#include <fairmq/tools/CppSTL.h>
 #include <fairmq/tools/Strings.h>
 
 #include <memory>
@@ -32,14 +31,6 @@ struct TransportError : std::runtime_error { using std::runtime_error::runtime_e
 
 } // namespace fair::mq
 
-namespace std
-{
-
-template<>
-struct hash<fair::mq::Transport> : fair::mq::tools::HashEnum<fair::mq::Transport> {};
-
-} /* namespace std */
-
 namespace fair::mq
 {
 

fairmq/tools/CppSTL.h

@@ -9,24 +9,10 @@
 #ifndef FAIR_MQ_TOOLS_CPPSTL_H
 #define FAIR_MQ_TOOLS_CPPSTL_H
 
-#include <functional>
-#include <memory>
-#include <type_traits>
-
 namespace fair::mq::tools
 {
 
-// provide an enum hasher to compensate std::hash not supporting enums in C++11
-template<typename Enum>
-struct HashEnum
-{
-    auto operator()(const Enum& e) const noexcept
-    -> typename std::enable_if<std::is_enum<Enum>::value, std::size_t>::type
-    {
-        using _type = typename std::underlying_type<Enum>::type;
-        return std::hash<_type>{}(static_cast<_type>(e));
-    }
-};
+
 
 } // namespace fair::mq::tools