E0358: 'declare' should not be written inside a 'declare namespace'

Inside declare namespace, declarations (functions, classes, etc.) are automatically declare. It is a syntax error to explicitly write declare on these declarations:

declare namespace jQuery {
  declare function get(url);
}

To fix this error, remove the declare keyword:

declare namespace jQuery {
  function get(url);
}

This bug is common in .d.ts files because many projects use skipLibCheck in tsconfig.json which disables TypeScript's checking of .d.ts files. We recommend fixing your .d.ts files as described above. If you disagree, please discuss this with the quick-lint-js maintainers.

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