#define SOL_ALL_SAFETIES_ON 1 #define SOL_ENABLE_INTEROP 1 // MUST be defined to use interop features #include #include #include // luwra, // another C++ wrapper library: // https://github.com/vapourismo/luwra struct ABC { ABC() : v_(0) { } ABC(int value) : v_(value) { } int value() const { return v_; } void setValue(int v) { v_ = v; } void overload1() { std::cout << "call overload1" << std::endl; } void overload2(int) { std::cout << "call overload2" << std::endl; } private: int v_; }; template inline bool sol_lua_interop_check(sol::types, lua_State* L, int relindex, sol::type index_type, Handler&& handler, sol::stack::record& tracking) { // just marking unused parameters for no compiler warnings (void)index_type; (void)handler; // using 1 element tracking.use(1); int index = lua_absindex(L, relindex); if (lua_getmetatable(L, index) == 1) { luaL_getmetatable(L, luwra::internal::UserTypeReg::name.c_str()); bool is_correct_type = lua_rawequal(L, -2, -1) == 1; lua_pop(L, 2); return is_correct_type; } return false; } template inline std::pair sol_lua_interop_get(sol::types t, lua_State* L, int relindex, void* unadjusted_pointer, sol::stack::record& tracking) { // you may not need to specialize this method every time: // some libraries are compatible with sol3's layout int index = lua_absindex(L, relindex); if (!sol_lua_interop_check(t, L, index, sol::type::userdata, sol::no_panic, tracking)) { return { false, nullptr }; } return { true, static_cast(unadjusted_pointer) }; } void register_sol_stuff(lua_State* L) { // grab raw state and put into state_view // state_view is cheap to construct sol::state_view lua(L); // bind and set up your things: everything is entirely self-contained lua["f"] = sol::overload( [](ABC& from_luwra) { std::cout << "calling 1-argument version with luwra-created ABC { " << from_luwra.value() << " }" << std::endl; sol_c_assert(from_luwra.value() == 24); }, [](ABC& from_luwra, int second_arg) { std::cout << "calling 2-argument version with luwra-created ABC { " << from_luwra.value() << " } and integer argument of " << second_arg << std::endl; sol_c_assert(from_luwra.value() == 24); sol_c_assert(second_arg == 5); }); } void check_with_sol(lua_State* L) { sol::state_view lua(L); ABC& obj = lua["obj"]; (void)obj; sol_c_assert(obj.value() == 24); } int main(int, char*[]) { std::cout << "=== interop example (luwra) ===" << std::endl; std::cout << "code modified from luwra's documentation examples: https://github.com/vapourismo/luwra" << std::endl; luwra::StateWrapper state; state.registerUserType("ABC", { LUWRA_MEMBER(ABC, value), LUWRA_MEMBER(ABC, setValue) }, {}); register_sol_stuff(state); state.runString(R"( obj = ABC(24) f(obj) -- call 1 argument version f(obj, 5) -- call 2 argument version )"); check_with_sol(state); return 0; }