动手做Get your hands on it
练习跟着课文走 —— 每节课尾都有本课的练习。这一页是全部练习的总库，想集中刷题的时候来。 每个练习都写清了它来自哪一节，卡住了就回去看那一节。Practice follows the lessons — every lesson ends with the exercises for that lesson. This page is the whole library, for when you want to drill in one sitting. Each exercise names the lesson it came from, so you can go back when you stall.
已筛到你正在学的《地基 · 项目与语言》。想看全部就点上面的「全部」。Filtered to Foundations · project and language — the course you are on. Use “All” above to see everything.
练习Exercises
筛出 16 个练习（共 148 个） · 第 2 / 2 页。Showing 16 of 148 · page 2 / 2.你在 node-subgraph/ 里跑 npm start, 服务器起不来。报错很长，但关键信息只有两行。
You run npm start inside node-subgraph/ and the server does not come up. The error is long, but only two lines of it matter.
这是 NoteTable 真实的 props 类型。 三个空：一个数组类型、一个函数类型的参数、一个函数类型的返回值。
This is the real props type of NoteTable. Three blanks: an array type, a parameter of a function type, and the return value of a function type.
你刚 clone 好 react-notes-app，一行代码都还没写，先跑了npm run build，得到 10 个TS2582: Cannot find name 'test'。 同时 npx vitest run 显示 4 个测试全过。 最合理的判断是？
You have just cloned react-notes-app, written not one line of code, and run npm run build. You get 10 of TS2582: Cannot find name 'test'. At the same time npx vitest run shows all 4 tests passing. What is the most sensible conclusion?
两处真实的泛型用法。想清楚「TypeScript 能不能自己推断出来」。
Two real uses of generics. For each one, work out whether TypeScript can infer it on its own.