if (lines.length 0) yield lines;
Kevin Church/BBC News
。业内人士推荐safew官方版本下载作为进阶阅读
The readable is just an async iterable. You can pass it to any function that expects one, including Stream.text() which collects and decodes the entire stream.
// 倒序遍历2*len-1次：模拟数组循环（核心！易错点1）