[cleanup] replace remove_pointer with std:: implementation

dune/common/test/typetraitstest.cc

@@ -26,12 +26,5 @@ int main() {
   assert(     Dune::is_lvalue_reference<int&>::value );
   assert( not Dune::is_lvalue_reference<int&&>::value );
 
-  // Test remove_pointer
-  assert( (Dune::is_same<int,       Dune::remove_pointer<int>::type>::value) );
-  assert( (Dune::is_same<int,       Dune::remove_pointer<int*>::type>::value) );
-  assert( (Dune::is_same<int*,      Dune::remove_pointer<int**>::type>::value) );
-  assert( (Dune::is_same<const int, Dune::remove_pointer<const int*>::type>::value) );
-  assert( (Dune::is_same<int,       Dune::remove_pointer<int* const>::type>::value) );
-
   return 0;
 }

dune/common/typetraits.hh

@@ -209,20 +209,7 @@ namespace Dune
   : public integral_constant<bool, (__is_lvalue_reference_helper<T>::value)>
     { };
 
-  template<typename _Tp>
-    struct __remove_pointer_helper
-    { typedef _Tp     type; };
-
-  template<typename _Tp>
-    struct __remove_pointer_helper<_Tp*>
-    { typedef _Tp     type; };
-
-  /** \brief Return the type a pointer type points to
-   */
-  template<typename _Tp>
-    struct remove_pointer
-    : public __remove_pointer_helper<typename remove_const<_Tp>::type >
-    { };
+  using std::remove_pointer;
 
   /**
      \brief template which always yields a false value