test/eigen: update test for returning reference

unittest/return_by_ref.cpp

@@ -20,6 +20,7 @@ struct Base
   }
   
   Matrix & ref() { return mat; }
+  const Matrix & const_ref() { return mat; }
   Matrix  copy() { return mat; }
   
 protected:
@@ -27,18 +28,30 @@ protected:
   Matrix mat;
 };
 
+template<typename MatrixType>
+void expose_matrix_class(const std::string & name)
+{
+  using namespace Eigen;
+  namespace bp = boost::python;
+  
+  bp::class_<Base<MatrixType> >(name.c_str(),bp::init<DenseIndex,DenseIndex>())
+  .def("show",&Base<MatrixType>::show)
+  .def("ref",&Base<MatrixType>::ref, bp::return_internal_reference<>())
+  .def("const_ref",&Base<MatrixType>::const_ref, bp::return_internal_reference<>())
+  .def("copy",&Base<MatrixType>::copy);
+}
 
 BOOST_PYTHON_MODULE(return_by_ref)
 {
   using namespace Eigen;
-  namespace bp = boost::python;
   eigenpy::enableEigenPy();
 
-  
+  typedef Eigen::Matrix<double,Eigen::Dynamic,1> VectorType;
+  typedef Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic> MatrixType;
   typedef Eigen::Matrix<double,Eigen::Dynamic,Eigen::Dynamic,Eigen::RowMajor> RowMatrixType;
-  bp::class_<Base<RowMatrixType> >("Matrix",bp::init<DenseIndex,DenseIndex>())
-  .def("show",&Base<RowMatrixType>::show)
-  .def("ref",&Base<RowMatrixType>::ref, bp::return_internal_reference<>())
-  .def("copy",&Base<RowMatrixType>::copy);
+  
+  expose_matrix_class<VectorType>("Vector");
+  expose_matrix_class<MatrixType>("Matrix");
+  expose_matrix_class<RowMatrixType>("RowMatrix");
 }