Remove some compat code from prolog.el

* lisp/progmodes/prolog.el (match-string): Remove alias to
function that always exists.

diff --git a/lisp/progmodes/prolog.el b/lisp/progmodes/prolog.el
index bdb98a47fa9ee9344a76bb5c5eb6c4e9d9c93049..a209d21807f53ea8abed0935e730b9ed55be0bd5 100644 (file)
--- a/lisp/progmodes/prolog.el
+++ b/lisp/progmodes/prolog.el
@@ -2748,20 +2748,6 @@ When called with prefix argument ARG, disable zipping instead."
                   (nth 1 state)))
         ))))
 
-;; For backward compatibility. Stolen from custom.el.
-(or (fboundp 'match-string)
-    ;; Introduced in Emacs 19.29.
-    (defun match-string (num &optional string)
-  "Return string of text matched by last search.
-NUM specifies which parenthesized expression in the last regexp.
- Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
-Zero means the entire text matched by the whole regexp or whole string.
-STRING should be given if the last search was by `string-match' on STRING."
-  (if (match-beginning num)
-      (if string
-          (substring string (match-beginning num) (match-end num))
-        (buffer-substring (match-beginning num) (match-end num))))))
-
 (defun prolog-pred-start ()
   "Return the starting point of the first clause of the current predicate."
   ;; FIXME: Use SMIE.