quick-lint-js

Find bugs in JavaScript programs.

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 {
  // ...
}

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