docs: Clarify usage of no-unreachable with TypeScript

[benj-dobs]

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• I have read the contributing guidelines.

What is the purpose of this pull request? (put an "X" next to an item)

[x] Documentation update
[ ] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofix to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

Closes: #18378

What changes did you make? (Give an overview)

I've updated the documentation for no-unreachable to clarify that TypeScript will only consider unreachable code an error if configured to do so.

I checked whether there are any differences in behaviour between TypeScript an ESLint. The only one I found was in this case:

function foo() {
  try {
    return;
  } catch (err) {
    return err;
  }
}

ESLint reports this catch block as unreachable, but TypeScript does not. I did not think this was worth documenting.

Is there anything you'd like reviewers to focus on?

I've included a link to the TypeScript documentation; let me know if you would prefer not to have it.

[linux-foundation-easycla]

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• ✅ login: benj-dobs (d48fc4a)

[eslint-github-bot]

Hi @benj-dobs!, thanks for the Pull Request

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[eslint-github-bot]

Hi @benj-dobs!, thanks for the Pull Request

The pull request title isn't properly formatted. We ask that you update the pull request title to match this format, as we use it to generate changelogs and automate releases.

• The commit message tag wasn't recognized. Did you mean "docs", "fix", or "feat"?
• There should be a space following the initial tag and colon, for example 'feat: Message'.
• The first letter of the tag should be in lowercase

To Fix: You can fix this problem by clicking 'Edit' next to the pull request title at the top of this page.

Read more about contributing to ESLint here

[mdjermanovic]

LGTM, thanks!