#include #include inline constexpr int magic_value = 24; using zero_arg_type = int (*)(); using one_arg_type = int (*)(int); using callback_type = int (*)(one_arg_type); int free_function(int value) { return value + 1; } int callback(one_arg_type f) { return f(magic_value) + 1; } int main() { constexpr int expected_value = magic_value; constexpr int expected_free_function_value = magic_value + 1; constexpr int expected_callback_value = magic_value + 1 + 1; sol::state lua; lua.open_libraries(sol::lib::base); auto lambda = []() { return magic_value; }; auto lambda_ptr = static_cast(lambda); lua["magic_value"] = magic_value; lua["expected_value"] = expected_value; lua["expected_free_function_value"] = expected_free_function_value; lua["expected_callback_value"] = expected_callback_value; lua["lambda"] = sol::as_function_reference(lambda); lua["lambda_ptr"] = lambda_ptr; lua["free_function"] = &free_function; lua["callback"] = &callback; zero_arg_type lambda_f = lua["lambda"]; zero_arg_type lambda_ptr_f = lua["lambda_ptr"]; one_arg_type free_function_f = lua["free_function"]; callback_type callback_f = lua["callback"]; sol::function lua_callback_f = lua["callback"]; int lambda_f_result = lambda_f(); int lambda_ptr_f_result = lambda_ptr_f(); int free_function_f_result = free_function_f(magic_value); int callback_f_result = callback_f(&free_function); int lua_callback_f_result = lua_callback_f(&free_function); sol_c_assert(lambda_f_result == expected_value); sol_c_assert(lambda_ptr_f_result == expected_value); sol_c_assert(free_function_f_result == expected_free_function_value); sol_c_assert(callback_f_result == expected_callback_value); sol_c_assert(lua_callback_f_result == expected_callback_value); const char code[] = R"( assert(lambda() == expected_value) assert(lambda_ptr() == expected_value) assert(free_function(magic_value) == expected_free_function_value) assert(callback(free_function) == expected_callback_value) )"; sol::optional err = lua.safe_script(code, sol::script_pass_on_error); if (err.has_value()) { std::cerr << err.value().what() << std::endl; return 1; } sol_c_assert(!err.has_value()); return 0; }