typescript编译报错

Question

初学typescript。成功安装了typescript，视图运行一个Hello TypeScript项目，成功编译了JS文件，但是有报错。

hello.ts文件：

function sayHello(person: string) {
    return 'Hello, ' + person;
}

let user:string = 'Tom';
console.log(sayHello(user));

ts版本：3.7.4：

报错信息如下：

error TS2688: Cannot find type definition file for 'accepts'.

error TS2688: Cannot find type definition file for 'body-parser'.

error TS2688: Cannot find type definition file for 'connect'.

error TS2688: Cannot find type definition file for 'cookies'.

error TS2688: Cannot find type definition file for 'cors'.

error TS2688: Cannot find type definition file for 'events'.

error TS2688: Cannot find type definition file for 'express'.

error TS2688: Cannot find type definition file for 'express-serve-static-core'.

error TS2688: Cannot find type definition file for 'fs-capacitor'.

error TS2688: Cannot find type definition file for 'glob'.

error TS2688: Cannot find type definition file for 'graphql-upload'.

error TS2688: Cannot find type definition file for 'http-assert'.

error TS2688: Cannot find type definition file for 'keygrip'.

error TS2688: Cannot find type definition file for 'koa'.

error TS2688: Cannot find type definition file for 'koa-compose'.

error TS2688: Cannot find type definition file for 'long'.

error TS2688: Cannot find type definition file for 'mime'.

error TS2688: Cannot find type definition file for 'minimatch'.

error TS2688: Cannot find type definition file for 'node-fetch'.

error TS2688: Cannot find type definition file for 'range-parser'.

error TS2688: Cannot find type definition file for 'serve-static'.

error TS2688: Cannot find type definition file for 'ws'.

error TS2688: Cannot find type definition file for 'zen-observable'.

Answer 1

解决方法：
先卸载typescript之前的版本3.7.4

npm uninstall typescript -g

再重新安装typescript最新版3.8.3，没有错误了，编译通过

npm install typescript -g

目前想到的唯一可能就是第一次安装的某个地方出错了。

Answer 2

第一种解决方法

1. 正确配置你的 typeRoots
```json
"typeRoots": [
   "node_modules/@types",
   "src/typings"
]
```
2. 安装缺少的类型

第二种解决方法为在 tsconfig.json中的 compilerOptions.skipLibCheck 设置为 true

{
  "compilerOptions": {
    "skipLibCheck": true
  }
}

我这边是全局安装的 typescript (yarn global add typescript) ，版本 3.8.2 并未报错，感觉还是和你本地有关系

Answer 3

我为什么把版本换成3.8.3了还会出现这个报错