Implement return data converter for bp::object return types, i.e. cre…

…ating Python object arrays as output.

include/boost/numpy/dstream/wiring/converter/return_to_core_shape_data.hpp

@@ -43,6 +43,7 @@
 #include <boost/mpl/and.hpp>
 #include <boost/mpl/assert.hpp>
 #include <boost/mpl/if.hpp>
+#include <boost/python/refcount.hpp>
 #include <boost/type_traits/is_scalar.hpp>
 #include <boost/type_traits/remove_reference.hpp>
 
@@ -98,15 +99,13 @@ struct scalar_return_to_core_shape_data_impl
             out_arr_value_t;
 
     scalar_return_to_core_shape_data_impl(
-        numpy::detail::iter & iter
+        numpy::detail::iter &                        iter
       , std::vector< std::vector<intptr_t> > const & out_core_shapes
     )
       : iter_(iter)
-      , out_core_shapes_(out_core_shapes)
     {
-        BOOST_ASSERT((out_core_shapes_.size()    == 1 &&
-                      out_core_shapes_[0].size() == 1 &&
-                      out_core_shapes_[0][0]     == 1));
+        BOOST_ASSERT((out_core_shapes.size()    == 1 &&
+                      out_core_shapes[0].size() == 0));
     }
 
     inline
@@ -120,7 +119,6 @@ struct scalar_return_to_core_shape_data_impl
     }
 
     numpy::detail::iter & iter_;
-    std::vector< std::vector<intptr_t> > const & out_core_shapes_;
 };
 
 template <class WiringModelAPI, class OutMapping, class RT>
@@ -154,6 +152,69 @@ struct select_scalar_return_to_core_shape_data_impl
             type;
 };
 
+//------------------------------------------------------------------------------
+template <class WiringModelAPI, class OutMapping, class RT>
+struct bp_object_return_to_core_shape_data_impl
+{
+    typedef bp_object_return_to_core_shape_data_impl<WiringModelAPI, OutMapping, RT>
+            type;
+
+    bp_object_return_to_core_shape_data_impl(
+        numpy::detail::iter &                        iter
+      , std::vector< std::vector<intptr_t> > const & out_core_shapes
+    )
+      : iter_(iter)
+    {
+        BOOST_ASSERT((out_core_shapes.size()    == 1 &&
+                      out_core_shapes[0].size() == 0));
+    }
+
+    inline
+    bool
+    operator()(RT const & obj)
+    {
+        uintptr_t * ptr_value_ptr = reinterpret_cast<uintptr_t *>(iter_.get_data(0));
+        // Increment the reference counter for the bp object so it does not get
+        // destroyed when the bp::object object gets out of scope.
+        *ptr_value_ptr = reinterpret_cast<uintptr_t>(python::xincref<PyObject>(obj.ptr()));
+
+        return true;
+    }
+
+    numpy::detail::iter & iter_;
+};
+
+template <class WiringModelAPI, class OutMapping, class RT>
+struct select_bp_object_return_to_core_shape_data_impl
+{
+    typedef mapping::detail::out_mapping<OutMapping>
+            out_mapping_utils;
+
+    // Check if the output arity is 1.
+    typedef typename out_mapping_utils::template arity_is_equal_to<1>::type
+            is_unary_out_mapping;
+
+    // Check if the output array has a scalar core shape.
+    typedef typename out_mapping_utils::template array<0>::is_scalar::type
+            is_scalar_out_array;
+
+    // Check if the output array has a bp::object data holding type.
+    typedef typename is_same<typename WiringModelAPI::template out_arr_value_type<0>::type, python::object>::type
+            is_bp_object_out_array_data_type;
+
+    typedef typename boost::mpl::if_<
+              typename boost::mpl::and_<
+                is_unary_out_mapping
+              , is_scalar_out_array
+              , is_bp_object_out_array_data_type
+              >::type
+            , bp_object_return_to_core_shape_data_impl<WiringModelAPI, OutMapping, RT>
+
+            , numpy::mpl::unspecified
+            >::type
+            type;
+};
+
 //------------------------------------------------------------------------------
 template <class VectorT, unsigned nd>
 struct get_multidim_std_vector_shape;
@@ -279,11 +340,16 @@ struct select_return_to_core_shape_data_converter
             , select_scalar_return_to_core_shape_data_impl<WiringModelAPI, OutMapping, RT>
 
             // TODO: Add bp::object types.
-            , typename boost::mpl::eval_if<
-                typename numpy::mpl::is_std_vector<bare_rt>::type
-              , std_vector_return_to_core_shape_data<WiringModelAPI, OutMapping, RT, RT, 1>
+            , typename boost::mpl::if_<
+                typename is_same<bare_rt, python::object>::type
+              , select_bp_object_return_to_core_shape_data_impl<WiringModelAPI, OutMapping, RT>
 
-              , numpy::mpl::unspecified
+              , typename boost::mpl::eval_if<
+                  typename numpy::mpl::is_std_vector<bare_rt>::type
+                , std_vector_return_to_core_shape_data<WiringModelAPI, OutMapping, RT, RT, 1>
+
+                , numpy::mpl::unspecified
+                >::type
               >::type
             >::type
             type;

include/boost/numpy/dstream/wiring/detail/utilities.hpp

@@ -64,6 +64,33 @@ struct all_out_arr_value_types_arity<WiringModelAPI, UnaryMetaFunction, 1>
             type;
 };
 
+template <
+    class WiringModelAPI
+  , template <class T> class UnaryMetaFunction
+  , unsigned out_arity
+>
+struct any_out_arr_value_type_arity;
+
+template <
+    class WiringModelAPI
+  , template <class T> class UnaryMetaFunction
+>
+struct any_out_arr_value_type_arity<WiringModelAPI, UnaryMetaFunction, 0>
+{
+    typedef boost::mpl::bool_<false>
+            type;
+};
+
+template <
+    class WiringModelAPI
+  , template <class T> class UnaryMetaFunction
+>
+struct any_out_arr_value_type_arity<WiringModelAPI, UnaryMetaFunction, 1>
+{
+    typedef typename UnaryMetaFunction< typename WiringModelAPI::template out_arr_value_type<0>::type >::type
+            type;
+};
+
 #define BOOST_PP_ITERATION_PARAMS_1 \
     (4, (2, BOOST_NUMPY_LIMIT_OUTPUT_ARITY, <boost/numpy/dstream/wiring/detail/utilities.hpp>, 1))
 #include BOOST_PP_ITERATE()
@@ -79,6 +106,15 @@ struct utilities
         typedef typename all_out_arr_value_types_arity<WiringModelAPI, UnaryMetaFunction, WiringModelAPI::mapping_definition_t::out::arity>::type
                 type;
     };
+
+    template <
+        template<class T> class UnaryMetaFunction
+    >
+    struct any_out_arr_value_type
+    {
+        typedef typename any_out_arr_value_type_arity<WiringModelAPI, UnaryMetaFunction, WiringModelAPI::mapping_definition_t::out::arity>::type
+                type;
+    };
 };
 
 }// namespace detail
@@ -117,6 +153,29 @@ struct all_out_arr_value_types_arity<WiringModelAPI, UnaryMetaFunction, OUT_ARIT
     #undef BOOST_NUMPY_DEF_pre_and
 };
 
+template <
+    class WiringModelAPI
+  , template <class T> class UnaryMetaFunction
+>
+struct any_out_arr_value_type_arity<WiringModelAPI, UnaryMetaFunction, OUT_ARITY>
+{
+    #define BOOST_NUMPY_DEF_pre_or(z, n, data) \
+        typename boost::mpl::or_<
+    #define BOOST_NUMPY_DEF_unary_metafunction_result(n) \
+        typename UnaryMetaFunction< typename WiringModelAPI::template out_arr_value_type<n>::type >::type
+    #define BOOST_NUMPY_DEF_post_or(z, n, data) \
+        BOOST_PP_COMMA() BOOST_NUMPY_DEF_unary_metafunction_result(BOOST_PP_ADD(n,1)) >::type
+
+    typedef BOOST_PP_REPEAT(BOOST_PP_SUB(OUT_ARITY,1), BOOST_NUMPY_DEF_pre_or, ~)
+            BOOST_NUMPY_DEF_unary_metafunction_result(0)
+            BOOST_PP_REPEAT(BOOST_PP_SUB(OUT_ARITY,1), BOOST_NUMPY_DEF_post_or, ~)
+            type;
+
+    #undef BOOST_NUMPY_DEF_post_or
+    #undef BOOST_NUMPY_DEF_unary_metafunction_result
+    #undef BOOST_NUMPY_DEF_pre_or
+};
+
 #undef OUT_ARITY
 
 #endif // BOOST_PP_ITERATION_FLAGS == 1

include/boost/numpy/dstream/wiring/generalized_wiring_model.hpp

@@ -26,6 +26,7 @@
 #include <boost/mpl/bitor.hpp>
 #include <boost/mpl/if.hpp>
 
+#include <boost/numpy/mpl/is_type_of.hpp>
 #include <boost/numpy/mpl/types_from_fctptr_signature.hpp>
 #include <boost/numpy/dstream/wiring.hpp>
 #include <boost/numpy/dstream/wiring/converter/arg_from_core_shape_data.hpp>
@@ -94,7 +95,10 @@ struct generalized_wiring_model_api
         // Note: This could lead to the requirement that
         //       the python GIL cannot released during the iteration!
         typedef typename boost::mpl::if_<
-                  typename LoopService::object_arrays_are_involved
+                  typename boost::mpl::or_<
+                    typename LoopService::object_arrays_are_involved
+                  , typename utilities< generalized_wiring_model_api<MappingDefinition, FTypes> >::template any_out_arr_value_type< numpy::mpl::is_type_of<python::object>::apply >::type
+                  >::type
                 , numpy::detail::iter::flags::REFS_OK
                 , numpy::detail::iter::flags::NONE
                 >::type

include/boost/numpy/mpl/is_type_of.hpp

@@ -0,0 +1,44 @@
+/**
+ * $Id$
+ *
+ * Copyright (C)
+ * 2014 - $Date$
+ *     Martin Wolf <[email protected]>
+ *
+ * \file    boost/numpy/mpl/is_type_of.hpp
+ * \version $Revision$
+ * \date    $Date$
+ * \author  Martin Wolf <[email protected]>
+ *
+ * \brief This file defines a MPL template for checking if a type T is the same
+ *        as type U using an unary metafunction for checking.
+ *
+ *        This file is distributed under the Boost Software License,
+ *        Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+ *        http://www.boost.org/LICENSE_1_0.txt).
+ */
+#ifndef BOOST_NUMPY_MPL_IS_TYPE_OF_HPP_INCLUDED
+#define BOOST_NUMPY_MPL_IS_TYPE_OF_HPP_INCLUDED
+
+#include <boost/type_traits/is_same.hpp>
+
+namespace boost {
+namespace numpy {
+namespace mpl {
+
+template <class U>
+struct is_type_of
+{
+    template <class T>
+    struct apply
+    {
+        typedef typename is_same<T, U>::type
+                type;
+    };
+};
+
+}// namespace mpl
+}// namespace numpy
+}// namespace boost
+
+#endif // ! BOOST_NUMPY_MPL_IS_TYPE_OF_HPP_INCLUDED