Once in a while in TypeScript code, you may come across a comment that looks something like this:
ts
// @ts-expect-errorletvalue : number = "oops!";
ts
// @ts-expect-errorletvalue : number = "oops!";
You may also know that // @ts-expect-error
suppresses type checking for a single line.
Wanting to ignore type errors might seem counterintuitive at first.
If a project already decided to use TypeScript, why disable type checking?
Rare cases do exist when TypeScript's type checking needs to be suppressed in a small area of code. TypeScript includes several "comment directives" that can change type checking behavior for a file or on a specific line. A comment directive is a comment that directs (changes) how a tool operates within a file.
This article will explain the kinds of comment directives supported by TypeScript: why they exist, what they do, and how to use them.