Merging fixes to release; Fixes #1427

[SVN r68076]

include/boost/iterator/transform_iterator.hpp

@@ -20,6 +20,8 @@
 #include <boost/type_traits/is_reference.hpp>
 #include <boost/type_traits/remove_const.hpp>
 #include <boost/type_traits/remove_reference.hpp>
+#include <boost/utility/result_of.hpp>
+
 
 #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1310))
 # include <boost/type_traits/is_base_and_derived.hpp>
@@ -35,33 +37,18 @@ namespace boost
 
   namespace detail 
   {
-
-    template <class UnaryFunc>
-    struct function_object_result
-    {
-      typedef typename UnaryFunc::result_type type;
-    };
-
-#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
-    template <class Return, class Argument>
-    struct function_object_result<Return(*)(Argument)>
-    {
-      typedef Return type;
-    };
-#endif
-
     // Compute the iterator_adaptor instantiation to be used for transform_iterator
     template <class UnaryFunc, class Iterator, class Reference, class Value>
     struct transform_iterator_base
     {
      private:
+        typedef typename std::iterator_traits<Iterator>::reference Arg1;
+
         // By default, dereferencing the iterator yields the same as
-        // the function.  Do we need to adjust the way
+        // the function.
-        // function_object_result is computed for the standard
-        // proposal (e.g. using Doug's result_of)?
         typedef typename ia_dflt_help<
             Reference
-          , function_object_result<UnaryFunc>
+          , result_of<UnaryFunc(typename std::iterator_traits<Iterator>::value_type)>
         >::type reference;
 
         // To get the default for Value: remove any reference on the
@@ -113,7 +100,7 @@ namespace boost
 #endif 
     }
 
-    template<
+    template <
         class OtherUnaryFunction
       , class OtherIterator
       , class OtherReference

test/transform_iterator_test.cpp

@@ -102,6 +102,16 @@ int mult_2(int arg)
   return arg*2;
 }
 
+struct polymorphic_mult_functor
+{
+    //Implement result_of protocol
+    template <class FArgs> struct result;
+    template <class F, class T> struct result<F(T)> {typedef T type;};
+
+    template <class T> 
+    typename result<polymorphic_mult_functor(T)>::type
+    operator()(const T& _arg) const {return _arg*2;}
+};
 
 int
 main()
@@ -244,5 +254,25 @@ main()
     );
   }
 
+  // Test transform_iterator with polymorphic object function
+  {
+    int x[N], y[N];
+    for (int k = 0; k < N; ++k)
+      x[k] = k;
+    std::copy(x, x + N, y);
+    
+    for (int k2 = 0; k2 < N; ++k2)
+      x[k2] = x[k2] * 2;
+    
+    boost::input_iterator_test(
+        boost::make_transform_iterator(y, polymorphic_mult_functor()), x[0], x[1]);
+
+    boost::input_iterator_test(
+        boost::make_transform_iterator(&y[0], polymorphic_mult_functor()), x[0], x[1]);
+ 
+    boost::random_access_readable_iterator_test(
+        boost::make_transform_iterator(y, polymorphic_mult_functor()), N, x);
+  }
+
   return boost::report_errors();
 }