recursive implicit conversion fails, although boost::python work at this situation #2182
Description
Issue description
recursive implicit conversion fails.
Reproducible example code
M.cpp:
#include <pybind11/pybind11.h>
struct S {
S(int) {}
};
struct E {
E(S) {}
};
struct T {
T(E) {}
};
namespace py = pybind11;
PYBIND11_MODULE(M, m) {
py::class_<S>(m, "S").def(py::init<int>());
py::implicitly_convertible<int, S>();
py::class_<E>(m, "E").def(py::init<S>());
py::implicitly_convertible<S, E>();
py::class_<T>(m, "T").def(py::init<E>());
}
main.py
from M import *
print("int -> S -> E -> T")
T(E(S(2333)))
print("int -> E -> T")
T(E(2333))
print("int -> S -> T")
T(S(2333))
print("int -> T")
T(2333)
what happen
the above three construction success but T(2333) fail. It say
int -> S -> E -> T
int -> E -> T
int -> S -> T
int -> T
Traceback (most recent call last):
File "main.py", line 9, in <module>
T(2333)
TypeError: __init__(): incompatible constructor arguments. The following argument types are supported:
1. M.T(arg0: M.E)
Invoked with: 2333
environment
arch linux
gcc 9.3.0
python 3.8.2
pybind11 2.5.0
what else
BTW boost::python works well at this situation
M.cpp
#include <boost/python.hpp>
struct S {
S(int) {}
};
struct E {
E(S) {}
};
struct T {
T(E) {}
};
namespace py = boost::python;
BOOST_PYTHON_MODULE(M) {
py::class_<S>("S", py::no_init).def(py::init<int>());
py::implicitly_convertible<int, S>();
py::class_<E>("E", py::no_init).def(py::init<S>());
py::implicitly_convertible<S, E>();
py::class_<T>("T", py::no_init).def(py::init<E>());
}