output_static_array transformer

Definition

“output_static_array” transformer works on native static arrays. It handles the translation between array and Python list object. Size of array should be predefined.

“output_static_array” transformer takes as first argument name or index of the original function argument. The argument should have “array” or “pointer” type. The second argument should an integer value, which represents array size.

Example

struct vector3{

    void get_values( int values[3] ){
        values[0] = x;
        values[1] = y;
        values[2] = z;
    }

    int x,y,z;
};

In order to expose get_values member function we need to create small wrapper. The following Py++ code does it for you:

from pyplusplus import module_builder
from pyplusplus import function_transformers as FT

mb = module_builder.module_builder_t( ... )
v3 = mb.class_( 'vector3' )
v3.mem_fun( 'get_values' ).add_transformation( FT.output_static_array( 0, 3 ) )

What you see below is the relevant pieces of generated code:

#include "__convenience.pypp.hpp" //Py++ header file, which contains few convenience function

namespace bp = boost::python;

static boost::python::object get_values_22786c66e5973b70f714e7662e2aecd2( ::ft::vector3 & inst ){
   int native_values[3];
   boost::python::list py_values;
   inst.get_values(native_values);
   pyplus_conv::copy_container( native_values, native_values + 3, pyplus_conv::list_inserter( py_values ) );
   return bp::object( py_values );
}

BOOST_PYTHON_MODULE(...){
    ...
    bp::class_< ft::vector3 >( "vector3", "documentation" )
       .def( "get_values"
             , &get_values_22786c66e5973b70f714e7662e2aecd2
             , ( bp::arg("inst") ) )
       .def_readwrite( "x", &ft::vector3::x )
       .def_readwrite( "y", &ft::vector3::y )
       .def_readwrite( "z", &ft::vector3::z );
}