fix `regexp-match-exact?' to work on paths, drop ports from docs

Closes PR 11213

collects/racket/private/string.rkt

@@ -451,7 +451,13 @@
       (and m (zero? (caar m))
            (= (cdar m)
               (cond [(bytes? s) (bytes-length s)]
-                    [(or (byte-regexp? p) (bytes? p)) (string-utf-8-length s)]
-                    [else (string-length s)])))))
+                    [(or (byte-regexp? p) (bytes? p)) 
+                     (if (path? s)
+                         (bytes-length (path->bytes s))
+                         (string-utf-8-length s))]
+                    [else 
+                     (if (path? s)
+                         (string-length (path->string s))
+                         (string-length s))])))))
 
   )

collects/scribblings/reference/regexps.scrbl

@@ -457,7 +457,7 @@ match succeeds, @racket[#f] otherwise.
 
 
 @defproc[(regexp-match-exact? [pattern (or/c string? bytes? regexp? byte-regexp?)]
-                              [input (or/c string? bytes? path? input-port?)])
+                              [input (or/c string? bytes? path?)])
           boolean?]{
 
 Like @racket[regexp-match?], but @racket[#t] is only returned when the