inout_static_array transformer

Definition

inout_static_array transformer is a combination of input and output transformers. It allows to call a C++ function, which takes an array using Python list class

“inout_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 specifies the array size.

Example

int sum_and_fill( int v[3], int value ){
    int result = v[0] + v[1] + v[2];
    v[0] = value;
    v[1] = value;
    v[2] = value;
    return result;
}

In order to expose sum_and_fill function we need to create a 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( ... )
sum_and_fill = mb.free_fun( 'sum_and_fill' )
sum_and_fill.add_transformation( ft.inout_static_array('v', 3) )

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

static boost::python::tuple sum_and_fill_2dd285a3344dbf7d71ffb7c78dd614c5( boost::python::object v, int value ){
    int native_v[3];
    boost::python::list py_v;
    pyplus_conv::ensure_uniform_sequence< int >( v, 3 );
    pyplus_conv::copy_sequence( v, pyplus_conv::array_inserter( native_v, 3 ) );
    int result = ::sum_and_fill(native_v, value);
    pyplus_conv::copy_container( native_v, native_v + 3, pyplus_conv::list_inserter( py_v ) );
    return bp::make_tuple( result, py_v );
}

BOOST_PYTHON_MODULE(ft_inout_static_array){
    { //::ft::sum_and_fill

        typedef boost::python::tuple ( *sum_and_fill_function_type )( boost::python::object,int );

        bp::def(
                 "sum_and_fill"
                 , sum_and_fill_function_type( &sum_and_fill_2dd285a3344dbf7d71ffb7c78dd614c5 )
                 , ( bp::arg("v"), bp::arg("value") ) );
    }
}

blog comments powered by Disqus

---