# E0214: use of undeclared type

A TypeScript type annotation must refer to a class, enum, generic parameter, interface, or type alias. It is an error to a type which does not exist:

    interface Response {
      ok: bool;
      error?: string;
      data?: object;
    }

    function padString(
      s: string,
      alignment: Alignment,
    ): string {
      /* ... */
    }

    const Title: FC = () => {
      return <h1>Welcome!</h1>;
    };

To fix this error, fix the name of the referenced type:

    interface Response {
      ok: boolean;
      error?: string;
      data?: object;
    }

Alternatively, declare the type:

    enum Alignment { LEFT, RIGHT, CENTER };

    function padString(
      s: string,
      alignment: Alignment,
    ): string {
      /* ... */
    }

Alternatively, import the type:

    import {type FC} from "react";

    const Title: FC = () => {
      return <h1>Welcome!</h1>;
    };

Introduced in quick-lint-js version 2.5.0.

Documentation for other errors