CL-PPCRE turns a PCRE string into a parse tree, as a native data structure, and the programmer has full access to this interface. For example, the sample regex:

    /(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/u

could be specified in your program as something like:

    ((:named-register "year" (:greedy-repetition 4 4 :digit-class))
     "-"
     (:named-register "month" (:greedy-repetition 2 2 :digit-class))
     "-"
     (:named-register "day" (:greedy-repetition 2 2 :digit-class)))

(Whether this is easier to read depends on your relative familiarity with CL and PCRE. It's a lot easier to generate or manipulate with native CL functions, though, if you ever need to do that.)

Most HLLs today wrap an existing C regular expression library, and I don't know any C regular expression library that provides a public interface to its parse tree, so it's unlikely that other languages will be able to do something similar without a lot of work.

Of course, regular-expressions-as-strings are still strings, so if you only need to write them, you can get most of the benefit by using your language's native string facilities: https://news.ycombinator.com/item?id=241373