# TypeScript

TypeScript 是 JavaScript 的超集，扩展了 JavaScript 的语法，因此现有的 JavaScript 代码可与 TypeScript 一起工作无需任何修改，TypeScript 通过类型注解提供编译时的静态类型检查。

TypeScript 可处理已有的 JavaScript 代码，并只对其中的 TypeScript 代码进行编译。

TypeScript 是一种给 JavaScript 添加特性的语言扩展。增加的功能包括：

* 类型批注和编译时类型检查
* 类型推断
* 类型擦除
* 接口
* 枚举
* Mixin
* 泛型编程
* 名字空间
* 元组
* Await

{% embed url="<https://www.zhihu.com/question/530099939/answer/2459663651>" %}


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