message: set_requires_gradient: don't allow implicit conversions
diff: @@ -31,6 +31,11 @@ PYBIND11_MODULE(enoki, m) {
  bind_pcg32(m);
  + m.def("set_requires_gradient",
  + [](py::object o, bool value) {
  + throw py::type_error("set_requires_gradient(): requires a differentiable type as input!");
  + }, "array"_a, "value"_a = true);
  +
  m.def("cuda_eval", &cuda_eval, "log_assembly"_a = false,
  py::call_guard<py::gil_scoped_release>());
  