diff --git a/src/include/helper_tools.cc.h b/src/include/helper_tools.cc.h
index 0f20a00..fc09571 100644
--- a/src/include/helper_tools.cc.h
+++ b/src/include/helper_tools.cc.h
@@ -65,22 +65,22 @@ namespace MultiArrayTools
 
     template <SpaceType STYPE, class Func, class... IndexTypes>
     auto mkGenMapI(const std::shared_ptr<Func>& f, std::shared_ptr<IndexTypes>... indices)
-	-> decltype( getIndex( mkGenMapR( f, indices->range()... ) ) )
+	-> decltype( getIndex( mkGenMapR<STYPE>( f, indices->range()... ) ) )
     {
-	auto mi = getIndex( mkGenMapR( f, indices->range()... ) );
+	auto mi = getIndex( mkGenMapR<STYPE>( f, indices->range()... ) );
 	(*mi)(indices...);
 	return mi;
     }
     
     template <class Func, class... RangeTypes>
-    auto mkMapR(const Func& f, std::shared_ptr<RangeTypes>... ranges)
+    auto mkMapR(const std::shared_ptr<Func>& f, std::shared_ptr<RangeTypes>... ranges)
 	-> decltype( mkGenMapR<SpaceType::ANY>(f, ranges... ) )
     {
         return mkGenMapR<SpaceType::ANY>(f, ranges... );
     }
 
     template <class Func, class... IndexTypes>
-    auto mkMapI(const Func& f, std::shared_ptr<IndexTypes>... indices)
+    auto mkMapI(const std::shared_ptr<Func>& f, std::shared_ptr<IndexTypes>... indices)
 	-> decltype( mkGenMapI<SpaceType::ANY>(f, indices... ) )
     {
         return mkGenMapI<SpaceType::ANY>(f, indices... );
diff --git a/src/include/helper_tools.h b/src/include/helper_tools.h
index 111d4fe..1eaa9a6 100644
--- a/src/include/helper_tools.h
+++ b/src/include/helper_tools.h
@@ -28,20 +28,20 @@ namespace MultiArrayTools
 	-> std::shared_ptr<MultiRange<RangeTypes...> >;
 
     template <SpaceType STYPE, class Func, class... RangeTypes>
-    auto mkGenMapR(const Func& f, std::shared_ptr<RangeTypes>... ranges)
+    auto mkGenMapR(const std::shared_ptr<Func>& f, std::shared_ptr<RangeTypes>... ranges)
 	-> std::shared_ptr<GenMapRange<FunctionalMultiArray<typename Func::value_type,Func,RangeTypes...>,
                                        STYPE,RangeTypes...> >;
 
     template <SpaceType STYPE, class Func, class... IndexTypes>
-    auto mkGenMapI(const Func& f, std::shared_ptr<IndexTypes>... indices)
+    auto mkGenMapI(const std::shared_ptr<Func>& f, std::shared_ptr<IndexTypes>... indices)
 	-> decltype( getIndex( mkGenMapR<STYPE>( f, indices->range()... ) ) );
 
     template <class Func, class... RangeTypes>
-    auto mkMapR(const Func& f, std::shared_ptr<RangeTypes>... ranges)
+    auto mkMapR(const std::shared_ptr<Func>& f, std::shared_ptr<RangeTypes>... ranges)
 	-> decltype( mkGenMapR<SpaceType::ANY>(f, ranges... ) );
 
     template <class Func, class... IndexTypes>
-    auto mkMapI(const Func& f, std::shared_ptr<IndexTypes>... indices)
+    auto mkMapI(const std::shared_ptr<Func>& f, std::shared_ptr<IndexTypes>... indices)
 	-> decltype( mkGenMapI<SpaceType::ANY>(f, indices... ) );
 
     template <class... IndexTypes>
diff --git a/src/include/map_range.cc.h b/src/include/map_range.cc.h
index 151982a..79492b3 100644
--- a/src/include/map_range.cc.h
+++ b/src/include/map_range.cc.h
@@ -1,6 +1,6 @@
 
 #include "map_range.h"
-#include <type_traits>
+//#include <type_traits>
 
 namespace MultiArrayTools
 {
@@ -398,8 +398,8 @@ namespace MultiArrayTools
         template <class MapF, class ORType>
         static void mk(std::shared_ptr<ORType>& outRange, MultiArray<size_t,ORType>& mapMult, const MapF& mapf)
         {
-            static_assert( std::is_same<size_t,typename MapF::value_type>::value,
-                           "out range value type for NONE must be size_t" );
+            //static_assert( std::is_same<size_t,typename MapF::value_type>::value,
+            //               "out range value type for NONE must be size_t" );
             size_t max = 0;
             for(auto ii = mapf.begin(); ii.max() != ii.pos(); ++ii) {
                 max = mapf[ii] > max ? mapf[ii]+1 : max;
@@ -529,7 +529,7 @@ namespace MultiArrayTools
     template <class MapF, SpaceType XSTYPE, class... Ranges>
     typename GenMapRange<MapF,XSTYPE,Ranges...>::IndexType GenMapRange<MapF,XSTYPE,Ranges...>::begin() const
     {
-	MapIndex<MapF,typename Ranges::IndexType...>
+	GenMapIndex<MapF,XSTYPE,typename Ranges::IndexType...>
 	    i( std::dynamic_pointer_cast<GenMapRange<MapF,XSTYPE,Ranges...> >
 	       ( std::shared_ptr<RangeBase>( RB::mThis ) ) );
 	i = 0;
@@ -539,7 +539,7 @@ namespace MultiArrayTools
     template <class MapF, SpaceType XSTYPE, class... Ranges>
     typename GenMapRange<MapF,XSTYPE,Ranges...>::IndexType GenMapRange<MapF,XSTYPE,Ranges...>::end() const
     {
-	MapIndex<MapF,typename Ranges::IndexType...>
+	GenMapIndex<MapF,XSTYPE,typename Ranges::IndexType...>
 	    i( std::dynamic_pointer_cast<GenMapRange<MapF,XSTYPE,Ranges...> >
 	       ( std::shared_ptr<RangeBase>( RB::mThis )) );
 	i = size();
diff --git a/src/include/ranges/range_types/classic_range.h b/src/include/ranges/range_types/classic_range.h
index a232bec..3a65fea 100644
--- a/src/include/ranges/range_types/classic_range.h
+++ b/src/include/ranges/range_types/classic_range.h
@@ -34,7 +34,8 @@ namespace MultiArrayTools
 	typedef typename RangeInterface<SingleIndex<size_t,SpaceType::NONE> >::IndexType IndexType;
 	typedef SingleRange<size_t,SpaceType::NONE> RangeType;
 	typedef size_t MetaType;
-	
+        typedef SingleRangeFactory<size_t,SpaceType::NONE> FType; 
+        
 	virtual size_t size() const final;
 	virtual size_t dim() const final;
 
diff --git a/src/include/ranges/range_types/null_range.h b/src/include/ranges/range_types/null_range.h
index 16e7c2c..968c0c0 100644
--- a/src/include/ranges/range_types/null_range.h
+++ b/src/include/ranges/range_types/null_range.h
@@ -41,6 +41,7 @@ namespace MultiArrayTools
 	typedef typename RangeInterface<SingleIndex<size_t,SpaceType::NUL> >::IndexType IndexType;
 	typedef SingleRange<size_t,SpaceType::NUL> RangeType;
 	typedef size_t MetaType;
+        typedef SingleRangeFactory<size_t,SpaceType::NUL> FType; 
 	
 	virtual size_t size() const final;
 	virtual size_t dim() const final;
diff --git a/src/include/ranges/range_types/space_range.h b/src/include/ranges/range_types/space_range.h
index 3187403..238afb5 100644
--- a/src/include/ranges/range_types/space_range.h
+++ b/src/include/ranges/range_types/space_range.h
@@ -33,6 +33,7 @@ namespace MultiArrayTools
 	typedef typename RangeInterface<SingleIndex<int,SpaceType::PSPACE> >::IndexType IndexType;
 	typedef SingleRange<int,SpaceType::PSPACE> RangeType;
 	typedef int MetaType;
+        typedef SingleRangeFactory<int,SpaceType::PSPACE> FType; 
 	
 	virtual size_t size() const final;
 	virtual size_t dim() const final;
diff --git a/src/include/ranges/range_types/spin_range.h b/src/include/ranges/range_types/spin_range.h
index 5fdfa5b..32c8dff 100644
--- a/src/include/ranges/range_types/spin_range.h
+++ b/src/include/ranges/range_types/spin_range.h
@@ -34,7 +34,8 @@ namespace MultiArrayTools
 	typedef typename RangeInterface<SingleIndex<size_t,SpaceType::SPIN> >::IndexType IndexType;
 	typedef SingleRange<size_t,SpaceType::SPIN> RangeType;
 	typedef size_t MetaType;
-	
+        typedef SingleRangeFactory<size_t,SpaceType::SPIN> FType; 
+        
 	virtual size_t size() const final;
 	virtual size_t dim() const final;