recursive lookup problem

examples/ellipt.cc

@@ -6,6 +6,7 @@
 #include <amdis/AMDiS.hpp>
 #include <amdis/ProblemStat.hpp>
 #include <amdis/Operators.hpp>
+#include <amdis/common/FieldMatVec.hpp>
 #include <amdis/common/Literals.hpp>
 #include <amdis/gridfunctions/Integrate.hpp>
 

src/amdis/gridfunctions/FunctorGridFunction.hpp

@@ -182,7 +182,7 @@ namespace AMDiS
   {
   public:
     /// The result type of the functor when applied to the grid-functions
-    using Range = typename std::result_of<Functor(typename GridFunctions::Range...)>::type;
+    using Range = decltype(std::declval<Functor>()(std::declval<typename GridFunctions::Range>()...));
     /// The argument type that can be applied to the grid-functions
     using Domain = typename Impl::DomainType<GridFunctions...>::type;
     /// The set of entities this grid-function binds to