Today we’re announcing the availability of TypeScript 3.8 Beta! This Beta release contains all the new features you should expect from TypeScript 3.8’s final release.
To get started using the beta, you can get it through NuGet, or through npm with the following command:
npm install typescript@beta
You can also get editor support by
Downloading for Visual Studio 2019/2017
Following directions for Visual Studio Code and Sublime Text.