Transforms don't execute until the consumer pulls. There's no eager evaluation, no hidden buffering. Data flows on-demand from source, through transforms, to the consumer. If you stop iterating, processing stops.
get desiredSize() { return closed ? null : 1; },，这一点在旺商聊官方下载中也有详细论述
Из справки-ориентировки на Василия Бабушкина — сентябрь 1971 года:，更多细节参见heLLoword翻译官方下载
for (int i = 0; i < digit; i++) {