Add simox::meta::hana_member_name

SimoxUtility/CMakeLists.txt

@@ -178,6 +178,7 @@ SET(INCLUDES
     meta/EnumNames.hpp
     meta/type_name.h
     meta/boost_hana/has_hana_accessor.h
+    meta/boost_hana/hana_member_name.h
     meta/type_traits/is_any_of.h
     meta/type_traits/is_std_array.h
     meta/type_traits/are_arithmetic.h

SimoxUtility/meta/boost_hana.h

@@ -2,4 +2,5 @@
 
 // This file is generated!
 
+#include "boost_hana/hana_member_name.h"
 #include "boost_hana/has_hana_accessor.h"

SimoxUtility/meta/boost_hana/hana_member_name.h

+#pragma once
+
+#include <boost/hana/core/to.hpp>
+
+#include "has_hana_accessor.h"
+
+namespace simox::meta::detail::_hana_member_name
+{
+    template<class CL, class MT, MT CL::* ptr>
+    struct helper
+    {
+        static_assert(has_hana_accessor_v<CL>, "The given type was not adapted by hana");
+
+        using accessor = boost::hana::accessors_impl<CL>;
+        using tuple = decltype(accessor::apply());
+        using member_ptr = boost::hana::struct_detail::member_ptr<MT CL::*, ptr>;
+
+        template<class...Ts>
+        struct search
+        {
+            static_assert(sizeof...(Ts), "Member not found");
+        };
+
+        template<class Name, class Ptr, class...Ts>
+        struct search<boost::hana::pair<Name, Ptr>, Ts...>
+        {
+            static constexpr const char* get()
+            {
+                if constexpr(std::is_same_v<Ptr, member_ptr>)
+                {
+                    return boost::hana::to<char const*>(Name{});
+                }
+                else
+                {
+                    return search<Ts...>::get();
+                }
+            }
+        };
+
+        template<class T>
+        struct search_init
+        {
+            static_assert(!std::is_same_v<T, T>, "The given type was not adapted by hana");
+        };
+        template<class...Ts>
+        struct search_init<boost::hana::tuple<Ts...>> : search<Ts...>
+        {};
+
+        static constexpr const char* name = search_init<tuple>::get();
+    };
+}
+
+namespace simox::meta
+{
+    template<class CL, class MT, MT CL::* ptr>
+    static constexpr const char* hana_member_name =
+        detail::_hana_member_name::helper<CL, MT, ptr>::name;
+}

SimoxUtility/tests/meta/BoostHana.cpp

+/**
+* @package    VirtualRobot
+* @author     Rainer Kartmann
+* @copyright  2018 Rainer Kartmann
+*/
+
+#define BOOST_TEST_MODULE SimoxUtility/meta/BoostHana
+
+#include <string>
+#include <iostream>
+
+#include <boost/test/included/unit_test.hpp>
+#include <boost/hana/adapt_struct.hpp>
+
+#include <SimoxUtility/meta/boost_hana.h>
+
+namespace hana = boost::hana;
+namespace ns
+{
+    struct Person
+    {
+        std::string name;
+        int age;
+    };
+}
+
+BOOST_HANA_ADAPT_STRUCT(ns::Person, name, age);
+
+BOOST_AUTO_TEST_CASE(test_hana_member_name)
+{
+    const auto name = simox::meta::hana_member_name<ns::Person, std::string, &ns::Person::name>;
+    const auto age  = simox::meta::hana_member_name<ns::Person, int,         &ns::Person::age>;
+    BOOST_CHECK_EQUAL("name", name);
+    BOOST_CHECK_EQUAL("age",  age);
+    std::cout << "name -> " << name << '\n';
+    std::cout << "age  -> " << age << '\n';
+}

SimoxUtility/tests/meta/CMakeLists.txt

 
 ADD_SU_TEST( EnumNames )
+ADD_SU_TEST( BoostHana )