I really like the way Common Lisp's ppcre library works: the functions all accept either standard strings or a s-expression version of the regular expression an

I really like the way Common Lisp's ppcre library works: the functions all accept either standard strings or a s-expression version of the regular expression and then, using compiler macros, all invocations with statically-determinable regular expressions get compiled to some internal representation at compile-time rather than generating that representation at run-time. http://weitz.de/cl-ppcre/#create-scanner2 http://weitz.de/cl-ppcre/#create-scanner2