[pfr_view] Fixed PFR limitation

Author: denzor200

test/sequence/pfr_fields_view.cpp

@@ -41,8 +41,7 @@ namespace ns {
 
     struct guaranteed_nonconstexpr_string {
         std::string value;
-        template<typename T>
-        /*explicit*/ guaranteed_nonconstexpr_string(T value) : value(std::move(value)) {
+        explicit guaranteed_nonconstexpr_string(std::string value) : value(std::move(value)) {
             std::cout << "mark to ensure nonconstexpr" << std::endl;
         }
     };
@@ -145,12 +144,14 @@ main()
 
 #if BOOST_PFR_USE_CPP17 != 0
     {
-        ns::employee emp{"John Doe", "jdoe"};
+        ns::employee emp{guaranteed_nonconstexpr_string("John Doe"),
+		                 guaranteed_nonconstexpr_string("jdoe")};
         pfr_fields_view<ns::employee> view(emp);
         std::cout << at_c<0>(view).value << std::endl;
         std::cout << at_c<1>(view).value << std::endl;
 
-        fusion::vector<ns::guaranteed_nonconstexpr_string, ns::guaranteed_nonconstexpr_string> v1("John Doe", "jdoe");
+        fusion::vector<ns::guaranteed_nonconstexpr_string, ns::guaranteed_nonconstexpr_string> v1(
+            guaranteed_nonconstexpr_string("John Doe"), guaranteed_nonconstexpr_string("jdoe"));
         BOOST_TEST(view == v1);
     }
 #endif // BOOST_PFR_USE_CPP17