Type Caster for std::vector<bool>

[maximiliank]

The Type Caster for STL std::vector<bool> is not working due to the following range based for loop:

nanobind/include/nanobind/stl/detail/nb_list.h

Line 62 in 90b2677

for (auto &value : src) {

See https://stackoverflow.com/a/34085592/9759769.

An example demonstrating the error would be:

#include <nanobind/nanobind.h>
#include <nanobind/stl/vector.h>
#include <vector>

namespace nb = nanobind;

using namespace nb::literals;


// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables, misc-use-anonymous-namespace, readability-identifier-length)
NB_MODULE(nanobind_example_ext, m)
{
    m.def("vector_bool", []() { return std::vector<bool>{false, true, false, true}; });
}

which yields on GCC 12.3.0:

[build] /nanobind_example/.venv/lib/python3.11/site-packages/nanobind/include/nanobind/stl/detail/nb_list.h:62:13: error: cannot bind non-const lvalue reference of type ‘std::_Bit_reference&’ to an rvalue of type ‘std::_Bit_iterator::reference’
[build]    62 |             for (auto &value : src) {
[build]       |             ^~~
[build] ninja: build stopped: subcommand failed.

[wjakob]

Closed via #256.