@GResourcePath(ui_config.RESOURCE_PATH ~ "main.ui")
    private struct UI {
        Window main_window;
        Stack left_menu;
        Stack main_stack;
    }
    private UI ui;
    this() {    
        ui.load_ui();
    }

void load_ui(UIStruct)(ref UIStruct ui) if (__traits(isPOD, UIStruct)) 
{
    auto attributes = __traits(getAttributes, UIStruct);
    static assert(attributes.length > 0 , "UIStruct must have path attribute");
    static if (is(typeof (attributes[0]) == GResourcePath)) {
        Builder builder = new Builder;
        builder.addFromResource(attributes[0].path);
        foreach (string id; FieldNameTuple!UIStruct)
        {
            auto temp = builder.getObject( id );
            if (temp is null) throw new BadGobjectIdException (id);
            mixin("ui." ~ id) = cast(typeof (mixin("ui." ~ id))) temp;
        }
    }
}