小编Pau*_*rts的帖子

将 TypeScript 包发布到 npm 以提供接受来自一个或另一个对等依赖项的输入的函数时，如何定义可选的对等依赖项？

import { ExternalFoo } from 'foo';
import { ExternalBar } from 'bar';

export const customPackage = (source: ExternalFoo | ExternalBar) => {
    /* ... */
}

当缺少两个选项之一时，如何防止使用我的包的人出错？

我想通过两个不同列的两个strtotime时间戳来订购一个mysql表.我有以下mysql命令:

SELECT * FROM (
(SELECT '1' AS `table`,  `vid_req_timestamp` AS `timestamp`, `title` FROM `movies` WHERE `vid_req` = '1')
UNION
(SELECT '2' AS `table`,  `ost_req_timestamp` AS `timestamp`, `title` FROM `movies` WHERE `ost_req` = '1')
)
ORDER BY `timestamp` DESC

这给了我一个错误:

#1248 - Every derived table must have its own alias

我想结合vid_req_timestamp,并ost_req_timestamp和使这些下降.知道时间戳来自何处(以某种方式)非常重要.