How do I pass a Python list of my object type ClassName
to a C++ function that accepts a vector<ClassName>
?
The best I found is something like this: example. Unfortunately, the code crashes and I can't seem to figure out why. Here's what I used:
template<typename T>
void python_to_vector(boost::python::object o, vector<T>* v) {
try {
object iter_obj = object(handle<>(PyObject_GetIter(o.ptr())));
return;
for (;;) {
object obj = extract<object>(iter_obj.attr("next")());
// Should launch an exception if it cannot extract T
v->emplace_back(extract<T>(obj));
}
} catch(error_already_set) {
PyErr_Clear();
// If there is an exception (no iterator, extract failed or end of the
// list reached), clear it and exit the function
return;
}
}
Assuming you have function that takes a std::vector<Foo>
void bar (std::vector<Foo> arg)
The easiest way to handle this is to expose the vector
to python.
BOOST_PYTHON_MODULE(awesome_module)
{
class_<Foo>("Foo")
//methods and attrs here
;
class_<std::vector<Foo> >("VectorOfFoo")
.def(vector_indexing_suite<std::vector<foo> >() )
;
.def("bar", &bar)
}
So now in python we can stick Foo
s into a vector
and pass the vector to bar
from awesome_module import *
foo_vector = VectorOfFoo()
foo_vector.extend(Foo(arg) for arg in arglist)
bar(foo_vector)
Found an iterator that solves my problem:
#include <boost/python/stl_iterator.hpp>
template<typename T>
void python_to_vector(boost::python::object o, vector<T>* v) {
stl_input_iterator<T> begin(o);
stl_input_iterator<T> end;
v->clear();
v->insert(v->end(), begin, end);
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With