That seems rather trivial, and I'm not sure how you could possibly have any issues with the borrow checker.
Just do the first regex search, then escape into a String with regex::escape, then build a regex from the String and search with it.
Of course what you are doing is probably wrong since you should use a string matching crate rather than escaping characters and using a regex matching crate.
Just do the first regex search, then escape into a String with regex::escape, then build a regex from the String and search with it.
Of course what you are doing is probably wrong since you should use a string matching crate rather than escaping characters and using a regex matching crate.