sol2/examples/require_dll_example/source/my_object.cpp

#include <my_object/my_object.hpp>

#define SOL_ALL_SAFETIES_ON 1
#include <sol/sol.hpp>

namespace my_object {

	sol::table open_my_object(sol::this_state L) {
		sol::state_view lua(L);
		sol::table module = lua.create_table();
		module.new_usertype<test>("test",
			sol::constructors<test(), test(int)>(),
			"value", &test::value);

		return module;
	}

} // namespace my_object

extern "C" int luaopen_my_object(lua_State* L) {
	// pass the lua_State,
	// the index to start grabbing arguments from,
	// and the function itself
	// optionally, you can pass extra arguments to the function if that's necessary,
	// but that's advanced usage and is generally reserved for internals only
	return sol::stack::call_lua(L, 1, my_object::open_my_object );
}