Twoslash

Ordinary TypeScript blocks receive syntax highlighting. Adding the twoslash metadata also runs TypeScript analysis during the documentation build and embeds its results in the generated HTML.

Type query

interface Completion {
  value: string;
  done: boolean;
}
 
const completion: Completion = { value: "ok", done: true };
 
const completion: Completioncompletion;
 

Expected diagnostic

const answer: number = "forty-two";
Type 'string' is not assignable to type 'number'.

Ordinary code block

This block is highlighted but is not passed through Twoslash:

const greeting: string = "hello";