field, err = dc.ReadMapKeyPtr()
		if err != nil {
			err = msgp.WrapError(err)
			return
		}
		switch msgp.UnsafeString(field) {
		case "ch":
			err = z.Children.DecodeMsg(dc)
			if err != nil {
				err = msgp.WrapError(err, "Children")
				return
			}
		case "sz":
			z.Size, err = dc.ReadInt64()
			if err != nil {
				err = msgp.WrapError(err, "Size")
				return
			}
		case "os":