[shared_ptr] Compile error with include "nanobind/stl/vector.h".

[huangweiwu]

I'm binding a function witch return a shared_ptr with the code below.
It's ok when not include "nanobind/stl/vector.h".
But when I include "nanobind/stl/vector.h", it comes up with compile error.
Binding 'shared_ptr' requires that 'T' can also be bound by nanobind. It appears that you specified a type which would undergo conversion/copying, which is not allowed.

std::shared_ptr<std::vector<float>> test_func(){
    std::shared_ptr<std::vector<float>> a;
    return a;
}

NB_MODULE(my_ext, m) {
    m.def("test_func", &test_func);
}

[wjakob]

This is correct. You can handle std::vector<> either as an opaque class binding (with stl/bind_vector.h, avoids copies) or as a type caster (with stl/vector.h, always copies). The std::shared_ptr support is only compatible with class bindings since the desire is obviously not to copy. It cannot be mixed with type casters.

[wjakob]

Please review this page to understand the differences: https://nanobind.readthedocs.io/en/latest/exchanging.html

[huangweiwu]

Get it!
Furthermore, stl/bind_vector.h and stl/vector.h can not be included in the same source file, is that right?

[wjakob]

Normally one or the other. Or you can include both and use NB_MAKE_OPAQUE to selectively disable the type caster for a particular flavor of std::vector.

[huangweiwu]

Get it! Thanks!