Function dfhack_event_newindex

library/LuaTools.cpp:1603–1635

}

static int dfhack_event_newindex(lua_State *L)
{
    luaL_checktype(L, 1, LUA_TUSERDATA);
    if (is_null_userdata(L, 2))
        luaL_argerror(L, 2, "Key NULL is reserved in events.");

    lua_settop(L, 3);
    lua_getuservalue(L, 1);
    bool new_nil = lua_isnil(L, 3);

    lua_pushvalue(L, 2);
    lua_rawget(L, 4);
    bool old_nil = lua_isnil(L, -1);
    lua_settop(L, 4);

    lua_pushvalue(L, 2);
    lua_pushvalue(L, 3);
    lua_rawset(L, 4);

    int delta = 0;
    if (old_nil && !new_nil) delta = 1;
    else if (new_nil && !old_nil) delta = -1;

    if (delta != 0)
    {
        auto obj = (EventObject *)lua_touserdata(L, 1);
        obj->item_count += delta;
        if (obj->owner)
            obj->owner->on_count_changed(obj->item_count, delta);
    }

    return 0;
}

static void do_invoke_event(lua_State *L, int argbase, int num_args, int errorfun)
{