# E0246: 'extends' must be before 'implements'

TypeScript classes can extend another class and implement interfaces. It is a syntax error to write the implemented interfaces before the extended class:

    import stream from "node:stream";
    class MyStream
        implements stream.ReadableStream
        extends stream.Stream {
      // ...
    }

To fix this error, write the `extends` clause before the `implements` clause:

    import stream from "node:stream";
    class MyStream
        extends stream.Stream
        implements stream.ReadableStream {
      // ...
    }

Introduced in quick-lint-js version 2.7.0.

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