Regex-validated string types (feedback reset)

This is a pickup of #6579. With the addition of #40336, a large number of those use cases have been addressed, but possibly some still remain.

Update 2023-04-11: Reviewed use cases and posted a write-up of our current evaluation

Search Terms

regex string types

Suggestion

Open question: For people who had upvoted #6579, what use cases still need addressing?

Note: Please keep discussion on-topic; moderation will be a bit heavier to avoid off-topic tangents

Examples

(please help)

Checklist

My suggestion meets these guidelines:

• [?] This wouldn't be a breaking change in existing TypeScript/JavaScript code
• [?] This wouldn't change the runtime behavior of existing JavaScript code
• [?] This could be implemented without emitting different JS based on the types of the expressions
• [?] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• [?] This feature would agree with the rest of TypeScript's Design Goals.

Start by reading the predecessor issue #6579, the changes in #40336, and the write-up linked in the 2023-04-11 update. Review the remaining use cases in the comment thread and establish a concrete proposal with examples; the issue does not define an implementation entry point or a clear completion criterion.