Function skr_check_unknown

modules/engine/lua/src/build.skr_lua.cpp:641–666

}

void* skr_check_unknown(lua_State *L, int index, std::string_view tid, std::string_view unknown)
{
    void *p = lua_touserdata(L, index);
    if (p != NULL) {  /* value is a userdata? */
        if (lua_getmetatable(L, index)) {  /* does it have a metatable? */
            luaL_getmetatable(L, tid.data());  /* get correct metatable */
            if (!lua_rawequal(L, -1, -2))  /* not the same? */
            {
                if(!unknown.empty()) /* check again */
                {
                    luaL_getmetatable(L, unknown.data());
                    if (!lua_rawequal(L, -1, -3))  /* not the same? */
                        p = NULL;  /* value is a userdata with wrong metatable */
                    lua_pop(L, 1);
                }
                else if(!lua_isnil(L, -1))
                {
                    p = NULL;
                }
            }
            lua_pop(L, 2);  /* remove both metatables */
        }
    }
    luaL_argexpected(L, p != 0, index, tid.data());
    return p;
}

void* check_unknown(lua_State *L, int index, std::string_view tid)
{