Initial revision
[bpt/emacs.git] / lisp / replace.el
index 488e1f1..ed02e05 100644 (file)
@@ -1,6 +1,6 @@
 ;;; replace.el --- replace commands for Emacs.
 
-;; Copyright (C) 1985, 1986, 1987, 1992 Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1986, 1987, 1992, 1994, 1996 Free Software Foundation, Inc.
 
 ;; This file is part of GNU Emacs.
 
@@ -15,8 +15,9 @@
 ;; GNU General Public License for more details.
 
 ;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING.  If not, write to
-;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; along with GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
 
 ;;; Commentary:
 
 
 ;;; Code:
 
-(defconst case-replace t "\
+(defvar case-replace t "\
 *Non-nil means query-replace should preserve case in replacements.")
 
 (defvar query-replace-history nil)
 
-(defun query-replace-read-args (string)
+(defvar query-replace-interactive nil
+  "Non-nil means `query-replace' uses the last search string.
+That becomes the \"string to replace\".")
+
+(defun query-replace-read-args (string regexp-flag)
   (let (from to)
-    (setq from (read-from-minibuffer (format "%s: " string)
-                                    nil nil nil
-                                    'query-replace-history))
+    (if query-replace-interactive
+       (setq from (car (if regexp-flag regexp-search-ring search-ring)))
+      (setq from (read-from-minibuffer (format "%s: " string)
+                                      nil nil nil
+                                      'query-replace-history)))
     (setq to (read-from-minibuffer (format "%s %s with: " string from)
                                   nil nil nil
                                   'query-replace-history))
 As each match is found, the user must type a character saying
 what to do with it.  For directions, type \\[help-command] at that time.
 
-Preserves case in each replacement if  case-replace  and  case-fold-search
+If `query-replace-interactive' is non-nil, the last incremental search
+string is used as FROM-STRING--you don't have to specify it with the
+minibuffer.
+
+Preserves case in each replacement if `case-replace' and `case-fold-search'
 are non-nil and FROM-STRING has no uppercase letters.
-Third arg DELIMITED (prefix arg if interactive) non-nil means replace
+\(Preserving case means that if the string matched is all caps, or capitalized,
+then its replacement is upcased or capitalized.)
+
+Third arg DELIMITED (prefix arg if interactive), if non-nil, means replace
 only matches surrounded by word boundaries.
 
 To customize possible responses, change the \"bindings\" in `query-replace-map'."
-  (interactive (query-replace-read-args "Query replace"))
-  (perform-replace from-string to-string t nil arg)
-  (or unread-command-events (message "Done")))
+  (interactive (query-replace-read-args "Query replace" nil))
+  (perform-replace from-string to-string t nil arg))
 (define-key esc-map "%" 'query-replace)
 
 (defun query-replace-regexp (regexp to-string &optional arg)
@@ -61,15 +74,19 @@ To customize possible responses, change the \"bindings\" in `query-replace-map'.
 As each match is found, the user must type a character saying
 what to do with it.  For directions, type \\[help-command] at that time.
 
-Preserves case in each replacement if  case-replace  and  case-fold-search
+If `query-replace-interactive' is non-nil, the last incremental search
+regexp is used as REGEXP--you don't have to specify it with the
+minibuffer.
+
+Preserves case in each replacement if `case-replace' and `case-fold-search'
 are non-nil and REGEXP has no uppercase letters.
-Third arg DELIMITED (prefix arg if interactive) non-nil means replace
+Third arg DELIMITED (prefix arg if interactive), if non-nil, means replace
 only matches surrounded by word boundaries.
-In TO-STRING, \\& means insert what matched REGEXP,
-and \\=\\<n> means insert what matched <n>th \\(...\\) in REGEXP."
-  (interactive (query-replace-read-args "Query replace regexp"))
-  (perform-replace regexp to-string t t arg)
-  (or unread-command-events (message "Done")))
+In TO-STRING, `\\&' stands for whatever matched the whole of REGEXP,
+and `\\=\\N' (where N is a digit) stands for
+ whatever what matched the Nth `\\(...\\)' in REGEXP."
+  (interactive (query-replace-read-args "Query replace regexp" t))
+  (perform-replace regexp to-string t t arg))
 
 (defun map-query-replace-regexp (regexp to-strings &optional arg)
   "Replace some matches for REGEXP with various strings, in rotation.
@@ -80,13 +97,18 @@ wrapping around from the last such string to the first.
 
 Non-interactively, TO-STRINGS may be a list of replacement strings.
 
+If `query-replace-interactive' is non-nil, the last incremental search
+regexp is used as REGEXP--you don't have to specify it with the minibuffer.
+
 A prefix argument N says to use each replacement string N times
 before rotating to the next."
   (interactive
    (let (from to)
-     (setq from (read-from-minibuffer "Map query replace (regexp): "
-                                     nil nil nil
-                                     'query-replace-history))
+     (setq from (if query-replace-interactive
+                   (car regexp-search-ring)
+                 (read-from-minibuffer "Map query replace (regexp): "
+                                       nil nil nil
+                                       'query-replace-history)))
      (setq to (read-from-minibuffer
               (format "Query replace %s with (space-separated strings): "
                       from)
@@ -106,42 +128,50 @@ before rotating to the next."
                                       (1+ (string-match " " to-strings))))
          (setq replacements (append replacements (list to-strings))
                to-strings ""))))
-    (perform-replace regexp replacements t t nil arg))
-  (or unread-command-events (message "Done")))
+    (perform-replace regexp replacements t t nil arg)))
 
 (defun replace-string (from-string to-string &optional delimited)
   "Replace occurrences of FROM-STRING with TO-STRING.
 Preserve case in each match if `case-replace' and `case-fold-search'
 are non-nil and FROM-STRING has no uppercase letters.
-Third arg DELIMITED (prefix arg if interactive) non-nil means replace
+\(Preserving case means that if the string matched is all caps, or capitalized,
+then its replacement is upcased or capitalized.)
+
+Third arg DELIMITED (prefix arg if interactive), if non-nil, means replace
 only matches surrounded by word boundaries.
 
+If `query-replace-interactive' is non-nil, the last incremental search
+string is used as FROM-STRING--you don't have to specify it with the
+minibuffer.
+
 This function is usually the wrong thing to use in a Lisp program.
 What you probably want is a loop like this:
-  (while (search-forward OLD-STRING nil t)
-    (replace-match REPLACEMENT nil t))
+  (while (search-forward FROM-STRING nil t)
+    (replace-match TO-STRING nil t))
 which will run faster and will not set the mark or print anything."
-  (interactive (query-replace-read-args "Replace string"))
-  (perform-replace from-string to-string nil nil delimited)
-  (or unread-command-events (message "Done")))
+  (interactive (query-replace-read-args "Replace string" nil))
+  (perform-replace from-string to-string nil nil delimited))
 
 (defun replace-regexp (regexp to-string &optional delimited)
   "Replace things after point matching REGEXP with TO-STRING.
-Preserve case in each match if case-replace and case-fold-search
+Preserve case in each match if `case-replace' and `case-fold-search'
 are non-nil and REGEXP has no uppercase letters.
-Third arg DELIMITED (prefix arg if interactive) non-nil means replace
+Third arg DELIMITED (prefix arg if interactive), if non-nil, means replace
 only matches surrounded by word boundaries.
-In TO-STRING, \\& means insert what matched REGEXP,
-and \\=\\<n> means insert what matched <n>th \\(...\\) in REGEXP.
+In TO-STRING, `\\&' stands for whatever matched the whole of REGEXP,
+and `\\=\\N' (where N is a digit) stands for
+ whatever what matched the Nth `\\(...\\)' in REGEXP.
+
+If `query-replace-interactive' is non-nil, the last incremental search
+regexp is used as REGEXP--you don't have to specify it with the minibuffer.
 
 This function is usually the wrong thing to use in a Lisp program.
 What you probably want is a loop like this:
   (while (re-search-forward REGEXP nil t)
-    (replace-match REPLACEMENT nil nil))
+    (replace-match TO-STRING nil nil))
 which will run faster and will not set the mark or print anything."
-  (interactive (query-replace-read-args "Replace regexp"))
-  (perform-replace regexp to-string nil t delimited)
-  (or unread-command-events (message "Done")))
+  (interactive (query-replace-read-args "Replace regexp" t))
+  (perform-replace regexp to-string nil t delimited))
 \f
 (defvar regexp-history nil
   "History list for some commands that read regular expressions.")
@@ -209,7 +239,9 @@ Applies to lines after point."
 (if occur-mode-map
     ()
   (setq occur-mode-map (make-sparse-keymap))
-  (define-key occur-mode-map "\C-c\C-c" 'occur-mode-goto-occurrence))
+  (define-key occur-mode-map [mouse-2] 'occur-mode-mouse-goto)
+  (define-key occur-mode-map "\C-c\C-c" 'occur-mode-goto-occurrence)
+  (define-key occur-mode-map "\C-m" 'occur-mode-goto-occurrence))
 
 (defvar occur-buffer nil)
 (defvar occur-nlines nil)
@@ -217,9 +249,10 @@ Applies to lines after point."
 
 (defun occur-mode ()
   "Major mode for output from \\[occur].
-Move point to one of the occurrences in this buffer,
-then use \\[occur-mode-goto-occurrence] to go to the same occurrence
-in the buffer that the occurrences were found in.
+\\<occur-mode-map>Move point to one of the items in this buffer, then use
+\\[occur-mode-goto-occurrence] to go to the occurrence that the item refers to.
+Alternatively, click \\[occur-mode-mouse-goto] on an item to go to it.
+
 \\{occur-mode-map}"
   (kill-all-local-variables)
   (use-local-map occur-mode-map)
@@ -227,29 +260,53 @@ in the buffer that the occurrences were found in.
   (setq mode-name "Occur")
   (make-local-variable 'occur-buffer)
   (make-local-variable 'occur-nlines)
-  (make-local-variable 'occur-pos-list))
+  (make-local-variable 'occur-pos-list)
+  (run-hooks 'occur-mode-hook))
 
-(defun occur-mode-goto-occurrence ()
-  "Go to the line this occurrence was found in, in the buffer it was found in."
-  (interactive)
+(defun occur-mode-mouse-goto (event)
+  "In Occur mode, go to the occurrence whose line you click on."
+  (interactive "e")
+  (let (buffer pos)
+    (save-excursion
+      (set-buffer (window-buffer (posn-window (event-end event))))
+      (save-excursion
+       (goto-char (posn-point (event-end event)))
+       (setq pos (occur-mode-find-occurrence))
+       (setq buffer occur-buffer)))
+    (pop-to-buffer buffer)
+    (goto-char (marker-position pos))))
+
+(defun occur-mode-find-occurrence ()
   (if (or (null occur-buffer)
          (null (buffer-name occur-buffer)))
       (progn
        (setq occur-buffer nil
              occur-pos-list nil)
        (error "Buffer in which occurrences were found is deleted")))
-  (let* ((occur-number (save-excursion
+  (let* ((line-count
+         (count-lines (point-min)
+                      (save-excursion
+                        (beginning-of-line)
+                        (point))))
+        (occur-number (save-excursion
                         (beginning-of-line)
-                        (/ (1- (count-lines (point-min)
-                                            (save-excursion
-                                              (beginning-of-line)
-                                              (point))))
+                        (/ (1- line-count)
                            (cond ((< occur-nlines 0)
                                   (- 2 occur-nlines))
                                  ((> occur-nlines 0)
                                   (+ 2 (* 2 occur-nlines)))
                                  (t 1)))))
         (pos (nth occur-number occur-pos-list)))
+    (if (< line-count 1)
+       (error "No occurrence on this line"))
+    (or pos
+       (error "No occurrence on this line"))
+    pos))
+
+(defun occur-mode-goto-occurrence ()
+  "Go to the occurrence the current line describes."
+  (interactive)
+  (let ((pos (occur-mode-find-occurrence)))
     (pop-to-buffer occur-buffer)
     (goto-char (marker-position pos))))
 \f
@@ -273,19 +330,26 @@ Interactively it is the prefix arg.
 The lines are shown in a buffer named `*Occur*'.
 It serves as a menu to find any of the occurrences in this buffer.
 \\[describe-mode] in that buffer will explain how."
-  (interactive (list (let* ((default (car regexp-history))
-                           (input 
-                            (read-from-minibuffer
-                             (format "List lines matching regexp (default `%s'): " default)
-                             nil nil nil
-                             'regexp-history)))
-                      (if (> (length input) 0) input
-                        (setcar regexp-history default)))
-                    current-prefix-arg))
-  (setq nlines (if nlines (prefix-numeric-value nlines)
-                list-matching-lines-default-context-lines))
-  (let ((first t)
+  (interactive
+   (list (let* ((default (car regexp-history))
+               (input
+                (read-from-minibuffer
+                 (if default
+                     (format "List lines matching regexp (default `%s'): "
+                             default)
+                   "List lines matching regexp: ")
+                 nil nil nil 'regexp-history)))
+          (if (string-equal input "")
+              default
+            (set-text-properties 0 (length input) nil input)
+            input))
+        current-prefix-arg))
+  (let ((nlines (if nlines
+                   (prefix-numeric-value nlines)
+                 list-matching-lines-default-context-lines))
+       (first t)
        (buffer (current-buffer))
+       (dir default-directory)
        (linenum 1)
        (prevpos (point-min))
        (final-context-start (make-marker)))
@@ -293,83 +357,110 @@ It serves as a menu to find any of the occurrences in this buffer.
 ;;;      (beginning-of-line)
 ;;;      (setq linenum (1+ (count-lines (point-min) (point))))
 ;;;      (setq prevpos (point)))
-    (with-output-to-temp-buffer "*Occur*"
-      (save-excursion
-       (set-buffer standard-output)
-       (insert "Lines matching ")
-       (prin1 regexp)
-       (insert " in buffer " (buffer-name buffer) ?. ?\n)
-       (occur-mode)
-       (setq occur-buffer buffer)
-       (setq occur-nlines nlines)
-       (setq occur-pos-list ()))
-      (if (eq buffer standard-output)
-         (goto-char (point-max)))
-      (save-excursion
-       (beginning-of-buffer)
-       ;; Find next match, but give up if prev match was at end of buffer.
-       (while (and (not (= prevpos (point-max)))
-                   (re-search-forward regexp nil t))
-         (goto-char (match-beginning 0))
-         (beginning-of-line)
-         (save-match-data
-           (setq linenum (+ linenum (count-lines prevpos (point)))))
-         (setq prevpos (point))
-         (goto-char (match-end 0))
-         (let* ((start (save-excursion
-                         (goto-char (match-beginning 0))
-                         (forward-line (if (< nlines 0) nlines (- nlines)))
-                         (point)))
-                (end (save-excursion
-                       (goto-char (match-end 0))
-                       (if (> nlines 0)
-                           (forward-line (1+ nlines))
-                           (forward-line 1))
-                       (point)))
-                (tag (format "%3d" linenum))
-                (empty (make-string (length tag) ?\ ))
-                tem)
-           (save-excursion
-             (setq tem (make-marker))
-             (set-marker tem (point))
-             (set-buffer standard-output)
-             (setq occur-pos-list (cons tem occur-pos-list))
-             (or first (zerop nlines)
-                 (insert "--------\n"))
-             (setq first nil)
-             (insert-buffer-substring buffer start end)
-             (backward-char (- end start))
-             (setq tem nlines)
-             (while (> tem 0)
-               (insert empty ?:)
-               (forward-line 1)
-               (setq tem (1- tem)))
-             (let ((this-linenum linenum))
-               (set-marker final-context-start
-                           (+ (point) (- (match-end 0) (match-beginning 0))))
-               (while (< (point) final-context-start)
-                 (if (null tag)
-                     (setq tag (format "%3d" this-linenum)))
-                 (insert tag ?:)
-                 (setq tag nil)
-                 (forward-line 1)
-                 (setq this-linenum (1+ this-linenum))))
-             (while (< tem nlines)
-               (insert empty ?:)
-               (forward-line 1)
-               (setq tem (1+ tem))))                           
-           (forward-line 1)))
-       (set-buffer standard-output)
-       ;; Put positions in increasing order to go with buffer.
-       (setq occur-pos-list (nreverse occur-pos-list))
-       (if (interactive-p)
-           (message "%d matching lines." (length occur-pos-list)))))))
+    (save-excursion
+      (goto-char (point-min))
+      ;; Check first whether there are any matches at all.
+      (if (not (re-search-forward regexp nil t))
+         (message "No matches for `%s'" regexp)
+       ;; Back up, so the search loop below will find the first match.
+       (goto-char (match-beginning 0))
+       (with-output-to-temp-buffer "*Occur*"
+         (save-excursion
+           (set-buffer standard-output)
+           (setq default-directory dir)
+           ;; We will insert the number of lines, and "lines", later.
+           (insert " matching ")
+           (let ((print-escape-newlines t))
+             (prin1 regexp))
+           (insert " in buffer " (buffer-name buffer) ?. ?\n)
+           (occur-mode)
+           (setq occur-buffer buffer)
+           (setq occur-nlines nlines)
+           (setq occur-pos-list ()))
+         (if (eq buffer standard-output)
+             (goto-char (point-max)))
+         (save-excursion
+           ;; Find next match, but give up if prev match was at end of buffer.
+           (while (and (not (= prevpos (point-max)))
+                       (re-search-forward regexp nil t))
+             (goto-char (match-beginning 0))
+             (beginning-of-line)
+             (save-match-data
+               (setq linenum (+ linenum (count-lines prevpos (point)))))
+             (setq prevpos (point))
+             (goto-char (match-end 0))
+             (let* ((start (save-excursion
+                             (goto-char (match-beginning 0))
+                             (forward-line (if (< nlines 0) nlines (- nlines)))
+                             (point)))
+                    (end (save-excursion
+                           (goto-char (match-end 0))
+                           (if (> nlines 0)
+                               (forward-line (1+ nlines))
+                               (forward-line 1))
+                           (point)))
+                    (tag (format "%5d" linenum))
+                    (empty (make-string (length tag) ?\ ))
+                    tem)
+               (save-excursion
+                 (setq tem (make-marker))
+                 (set-marker tem (point))
+                 (set-buffer standard-output)
+                 (setq occur-pos-list (cons tem occur-pos-list))
+                 (or first (zerop nlines)
+                     (insert "--------\n"))
+                 (setq first nil)
+                 (insert-buffer-substring buffer start end)
+                 (set-marker final-context-start 
+                             (- (point) (- end (match-end 0))))
+                 (backward-char (- end start))
+                 (setq tem nlines)
+                 (while (> tem 0)
+                   (insert empty ?:)
+                   (forward-line 1)
+                   (setq tem (1- tem)))
+                 (let ((this-linenum linenum))
+                   (while (< (point) final-context-start)
+                     (if (null tag)
+                         (setq tag (format "%5d" this-linenum)))
+                     (insert tag ?:)
+                     (put-text-property (save-excursion
+                                          (beginning-of-line)
+                                          (point))
+                                        (save-excursion
+                                          (end-of-line)
+                                          (point))
+                                        'mouse-face 'highlight)
+                     (forward-line 1)
+                     (setq tag nil)
+                     (setq this-linenum (1+ this-linenum)))
+                   (while (<= (point) final-context-start)
+                     (insert empty ?:)
+                     (forward-line 1)
+                     (setq this-linenum (1+ this-linenum))))
+                 (while (< tem nlines)
+                   (insert empty ?:)
+                   (forward-line 1)
+                   (setq tem (1+ tem)))
+                 (goto-char (point-max)))
+               (forward-line 1)))
+           (set-buffer standard-output)
+           ;; Put positions in increasing order to go with buffer.
+           (setq occur-pos-list (nreverse occur-pos-list))
+           (goto-char (point-min))
+           (let ((message-string
+                  (if (= (length occur-pos-list) 1)
+                      "1 line"
+                    (format "%d lines" (length occur-pos-list)))))
+             (insert message-string)
+             (if (interactive-p)
+                 (message "%s matched" message-string)))))))))
 \f
 ;; It would be nice to use \\[...], but there is no reasonable way
 ;; to make that display both SPC and Y.
 (defconst query-replace-help
   "Type Space or `y' to replace one match, Delete or `n' to skip to next,
-ESC or `q' to exit, Period to replace one match and exit,
+RET or `q' to exit, Period to replace one match and exit,
 Comma to replace but not move point immediately,
 C-r to enter recursive edit (\\[exit-recursive-edit] to get out again),
 C-w to delete match and recursive edit,
@@ -383,7 +474,7 @@ C-l to clear the screen, redisplay, and offer same replacement again,
 The \"bindings\" in this map are not commands; they are answers.
 The valid answers include `act', `skip', `act-and-show',
 `exit', `act-and-exit', `edit', `delete-and-edit', `recenter',
-`automatic', `backup', and `help'.")
+`automatic', `backup', `exit-prefix', and `help'.")
 
 (define-key query-replace-map " " 'act)
 (define-key query-replace-map "\d" 'skip)
@@ -391,9 +482,12 @@ The valid answers include `act', `skip', `act-and-show',
 (define-key query-replace-map [backspace] 'skip)
 (define-key query-replace-map "y" 'act)
 (define-key query-replace-map "n" 'skip)
+(define-key query-replace-map "Y" 'act)
+(define-key query-replace-map "N" 'skip)
 (define-key query-replace-map "," 'act-and-show)
-(define-key query-replace-map "\e" 'exit)
 (define-key query-replace-map "q" 'exit)
+(define-key query-replace-map "\r" 'exit)
+(define-key query-replace-map [return] 'exit)
 (define-key query-replace-map "." 'act-and-exit)
 (define-key query-replace-map "\C-r" 'edit)
 (define-key query-replace-map "\C-w" 'delete-and-edit)
@@ -401,9 +495,13 @@ The valid answers include `act', `skip', `act-and-show',
 (define-key query-replace-map "!" 'automatic)
 (define-key query-replace-map "^" 'backup)
 (define-key query-replace-map "\C-h" 'help)
+(define-key query-replace-map [f1] 'help)
+(define-key query-replace-map [help] 'help)
 (define-key query-replace-map "?" 'help)
 (define-key query-replace-map "\C-g" 'quit)
 (define-key query-replace-map "\C-]" 'quit)
+(define-key query-replace-map "\e" 'exit-prefix)
+(define-key query-replace-map [escape] 'exit-prefix)
 
 (defun perform-replace (from-string replacements
                        query-flag regexp-flag delimited-flag
@@ -413,8 +511,10 @@ Don't use this in your own program unless you want to query and set the mark
 just as `query-replace' does.  Instead, write a simple loop like this:
   (while (re-search-forward \"foo[ \t]+bar\" nil t)
     (replace-match \"foobar\" nil nil))
-which will run faster and do exactly what you probably want."
+which will run faster and probably do exactly what you want."
   (or map (setq map query-replace-map))
+  (and query-flag minibuffer-auto-raise
+       (raise-frame (window-frame (minibuffer-window))))
   (let ((nocasify (not (and case-fold-search case-replace
                            (string-equal from-string
                                          (downcase from-string)))))
@@ -429,7 +529,11 @@ which will run faster and do exactly what you probably want."
        (next-rotate-count 0)
        (replace-count 0)
        (lastrepl nil)                  ;Position after last match considered.
-       (match-again t))
+       (match-again t)
+       (message
+        (if query-flag
+            (substitute-command-keys
+             "Query replacing %s with %s: (\\<query-replace-map>\\[help] for help) "))))
     (if (stringp replacements)
        (setq next-replacement replacements)
       (or repeat-count (setq repeat-count 1)))
@@ -441,133 +545,177 @@ which will run faster and do exactly what you probably want."
                                    "\\b")))
     (push-mark)
     (undo-boundary)
-    ;; Loop finding occurrences that perhaps should be replaced.
-    (while (and keep-going
-               (not (eobp))
-               (funcall search-function search-string nil t)
-               ;; If the search string matches immediately after
-               ;; the previous match, but it did not match there
-               ;; before the replacement was done, ignore the match.
-               (if (or (eq lastrepl (point))
-                       (and regexp-flag
-                            (eq lastrepl (match-beginning 0))
-                            (not match-again)))
-                   (if (eobp)
-                       nil
-                     ;; Don't replace the null string 
-                     ;; right after end of previous replacement.
-                     (forward-char 1)
-                     (funcall search-function search-string nil t))
-                 t))
-
-      ;; Save the data associated with the real match.
-      (setq real-match-data (match-data))
-
-      ;; Before we make the replacement, decide whether the search string
-      ;; can match again just after this match.
-      (if regexp-flag
-         (setq match-again (looking-at search-string)))
-      ;; If time for a change, advance to next replacement string.
-      (if (and (listp replacements)
-              (= next-rotate-count replace-count))
-         (progn
-           (setq next-rotate-count
-                 (+ next-rotate-count repeat-count))
-           (setq next-replacement (nth replacement-index replacements))
-           (setq replacement-index (% (1+ replacement-index) (length replacements)))))
-      (if (not query-flag)
-         (progn
-           (store-match-data real-match-data)
-           (replace-match next-replacement nocasify literal)
-           (setq replace-count (1+ replace-count)))
-       (undo-boundary)
-       (let (done replaced key def)
-         ;; Loop reading commands until one of them sets done,
-         ;; which means it has finished handling this occurrence.
-         (while (not done)
-           (message "Query replacing %s with %s: "
-                    from-string next-replacement)
-           (setq key (read-event))
-           (setq key (vector key))
-           (setq def (lookup-key map key))
-           ;; Restore the match data while we process the command.
-           (store-match-data real-match-data)
-           (cond ((eq def 'help)
-                  (with-output-to-temp-buffer "*Help*"
-                    (princ
-                     (concat "Query replacing "
-                             (if regexp-flag "regexp " "")
-                             from-string " with "
-                             next-replacement ".\n\n"
-                             (substitute-command-keys
-                              query-replace-help)))))
-                 ((eq def 'exit)
-                  (setq keep-going nil)
-                  (setq done t))
-                 ((eq def 'backup)
-                  (let ((elt (car stack)))
-                    (goto-char (car elt))
-                    (setq replaced (eq t (cdr elt)))
-                    (or replaced
-                        (store-match-data (cdr elt)))
-                    (setq stack (cdr stack))))              
-                 ((eq def 'act)
-                  (or replaced
-                      (replace-match next-replacement nocasify literal))
-                  (setq done t replaced t))
-                 ((eq def 'act-and-exit)
-                  (or replaced
-                      (replace-match next-replacement nocasify literal))
-                  (setq keep-going nil)
-                  (setq done t replaced t))
-                 ((eq def 'act-and-show)
-                  (if (not replaced)
-                      (progn
-                        (replace-match next-replacement nocasify literal)
-                        (setq replaced t))))
-                 ((eq def 'automatic)
-                  (or replaced
-                      (replace-match next-replacement nocasify literal))
-                  (setq done t query-flag nil replaced t))
-                 ((eq def 'skip)
-                  (setq done t))
-                 ((eq def 'recenter)
-                  (recenter nil))
-                 ((eq def 'edit)
-                  (store-match-data
-                   (prog1 (match-data)
-                     (save-excursion (recursive-edit))))
-                  ;; Before we make the replacement,
-                  ;; decide whether the search string
-                  ;; can match again just after this match.
-                  (if regexp-flag
-                      (setq match-again (looking-at search-string))))
-                 ((eq def 'delete-and-edit)
-                  (delete-region (match-beginning 0) (match-end 0))
-                  (store-match-data
-                   (prog1 (match-data)
-                     (save-excursion (recursive-edit))))
-                  (setq replaced t))
-                 (t
-                  (setq keep-going nil)
-                  (setq unread-command-events
-                        (append (listify-key-sequence key)
-                                unread-command-events))
-                  (setq done t))))
-         ;; Record previous position for ^ when we move on.
-         ;; Change markers to numbers in the match data
-         ;; since lots of markers slow down editing.
-         (setq stack
-               (cons (cons (point)
-                           (or replaced
-                               (mapcar
-                                (function (lambda (elt)
-                                            (and elt
-                                                 (marker-position elt))))
-                                (match-data))))
-                     stack))
-         (if replaced (setq replace-count (1+ replace-count)))))
-      (setq lastrepl (point)))
-  (and keep-going stack)))
+    (unwind-protect
+       ;; Loop finding occurrences that perhaps should be replaced.
+       (while (and keep-going
+                   (not (eobp))
+                   (funcall search-function search-string nil t)
+                   ;; If the search string matches immediately after
+                   ;; the previous match, but it did not match there
+                   ;; before the replacement was done, ignore the match.
+                   (if (or (eq lastrepl (point))
+                           (and regexp-flag
+                                (eq lastrepl (match-beginning 0))
+                                (not match-again)))
+                       (if (eobp)
+                           nil
+                         ;; Don't replace the null string 
+                         ;; right after end of previous replacement.
+                         (forward-char 1)
+                         (funcall search-function search-string nil t))
+                     t))
+
+         ;; Save the data associated with the real match.
+         ;; For speed, use only integers and reuse the list used last time.
+         (setq real-match-data (match-data t real-match-data))
+
+         ;; Before we make the replacement, decide whether the search string
+         ;; can match again just after this match.
+         (if regexp-flag
+             (setq match-again (looking-at search-string)))
+         ;; If time for a change, advance to next replacement string.
+         (if (and (listp replacements)
+                  (= next-rotate-count replace-count))
+             (progn
+               (setq next-rotate-count
+                     (+ next-rotate-count repeat-count))
+               (setq next-replacement (nth replacement-index replacements))
+               (setq replacement-index (% (1+ replacement-index) (length replacements)))))
+         (if (not query-flag)
+             (progn
+               (store-match-data real-match-data)
+               (replace-match next-replacement nocasify literal)
+               (setq replace-count (1+ replace-count)))
+           (undo-boundary)
+           (let (done replaced key def)
+             ;; Loop reading commands until one of them sets done,
+             ;; which means it has finished handling this occurrence.
+             (while (not done)
+               (store-match-data real-match-data)
+               (replace-highlight (match-beginning 0) (match-end 0))
+               ;; Bind message-log-max so we don't fill up the message log
+               ;; with a bunch of identical messages.
+               (let ((message-log-max nil))
+                 (message message from-string next-replacement))
+               (setq key (read-event))
+               (setq key (vector key))
+               (setq def (lookup-key map key))
+               ;; Restore the match data while we process the command.
+               (cond ((eq def 'help)
+                      (with-output-to-temp-buffer "*Help*"
+                        (princ
+                         (concat "Query replacing "
+                                 (if regexp-flag "regexp " "")
+                                 from-string " with "
+                                 next-replacement ".\n\n"
+                                 (substitute-command-keys
+                                  query-replace-help)))
+                        (save-excursion
+                          (set-buffer standard-output)
+                          (help-mode))))
+                     ((eq def 'exit)
+                      (setq keep-going nil)
+                      (setq done t))
+                     ((eq def 'backup)
+                      (if stack
+                          (let ((elt (car stack)))
+                            (goto-char (car elt))
+                            (setq replaced (eq t (cdr elt)))
+                            (or replaced
+                                (store-match-data (cdr elt)))
+                            (setq stack (cdr stack)))
+                        (message "No previous match")
+                        (ding 'no-terminate)
+                        (sit-for 1)))
+                     ((eq def 'act)
+                      (or replaced
+                          (progn
+                            (replace-match next-replacement nocasify literal)
+                            (setq replace-count (1+ replace-count))))
+                      (setq done t replaced t))
+                     ((eq def 'act-and-exit)
+                      (or replaced
+                          (progn
+                            (replace-match next-replacement nocasify literal)
+                            (setq replace-count (1+ replace-count))))
+                      (setq keep-going nil)
+                      (setq done t replaced t))
+                     ((eq def 'act-and-show)
+                      (if (not replaced)
+                          (progn
+                            (replace-match next-replacement nocasify literal)
+                            (setq replace-count (1+ replace-count))
+                            (setq replaced t))))
+                     ((eq def 'automatic)
+                      (or replaced
+                          (progn
+                            (replace-match next-replacement nocasify literal)
+                            (setq replace-count (1+ replace-count))))
+                      (setq done t query-flag nil replaced t))
+                     ((eq def 'skip)
+                      (setq done t))
+                     ((eq def 'recenter)
+                      (recenter nil))
+                     ((eq def 'edit)
+                      (store-match-data
+                       (prog1 (match-data)
+                         (save-excursion (recursive-edit))))
+                      ;; Before we make the replacement,
+                      ;; decide whether the search string
+                      ;; can match again just after this match.
+                      (if regexp-flag
+                          (setq match-again (looking-at search-string))))
+                     ((eq def 'delete-and-edit)
+                      (delete-region (match-beginning 0) (match-end 0))
+                      (store-match-data
+                       (prog1 (match-data)
+                         (save-excursion (recursive-edit))))
+                      (setq replaced t))
+                     ;; Note: we do not need to treat `exit-prefix'
+                     ;; specially here, since we reread
+                     ;; any unrecognized character.
+                     (t
+                      (setq this-command 'mode-exited)
+                      (setq keep-going nil)
+                      (setq unread-command-events
+                            (append (listify-key-sequence key)
+                                    unread-command-events))
+                      (setq done t))))
+             ;; Record previous position for ^ when we move on.
+             ;; Change markers to numbers in the match data
+             ;; since lots of markers slow down editing.
+             (setq stack
+                   (cons (cons (point)
+                               (or replaced (match-data t)))
+                         stack))))
+         (setq lastrepl (point)))
+      (replace-dehighlight))
+    (or unread-command-events
+       (message "Replaced %d occurrence%s"
+                replace-count
+                (if (= replace-count 1) "" "s")))
+    (and keep-going stack)))
+
+(defvar query-replace-highlight nil
+  "*Non-nil means to highlight words during query replacement.")
+
+(defvar replace-overlay nil)
+
+(defun replace-dehighlight ()
+  (and replace-overlay
+       (progn
+        (delete-overlay replace-overlay)
+        (setq replace-overlay nil))))
+
+(defun replace-highlight (start end)
+  (and query-replace-highlight
+       (progn
+        (or replace-overlay
+            (progn
+              (setq replace-overlay (make-overlay start end))
+              (overlay-put replace-overlay 'face
+                           (if (internal-find-face 'query-replace)
+                               'query-replace 'region))))
+        (move-overlay replace-overlay start end (current-buffer)))))
 
 ;;; replace.el ends here