*** empty log message ***

[bpt/emacs.git] / lisp / delsel.el

diff --git a/lisp/delsel.el b/lisp/delsel.el
index bc93654..b1f1151 100644 (file)
--- a/lisp/delsel.el
+++ b/lisp/delsel.el
@@ -35,7 +35,7 @@
 
 ;; Commands which will delete the selection need a 'delete-selection
 ;; property on their symbols; commands which insert text but don't
-;; have this property won't delete the selction.  It can be one of
+;; have this property won't delete the selection.  It can be one of
 ;; the values:
 ;;  'yank
 ;;      For commands which do a yank; ensures the region about to be
@@ -87,12 +87,14 @@ any selection."
          (cond ((eq type 'kill)
                 (delete-active-region t))
                ((eq type 'yank)
-                ;; Before a yank command,
-                ;; make sure we don't yank the same region
-                ;; that we are going to delete.
+                ;; Before a yank command, make sure we don't yank the
+                ;; head of the kill-ring that really comes from the
+                ;; currently active region we are going to delete.
                 ;; That would make yank a no-op.
-                (when (string= (buffer-substring-no-properties (point) (mark))
-                               (car kill-ring))
+                (when (and (string= (buffer-substring-no-properties (point) (mark))
+                                    (car kill-ring))
+                           (fboundp 'mouse-region-match)
+                           (mouse-region-match))
                   (current-kill 1))
                 (delete-active-region))
                ((eq type 'supersede)
@@ -111,7 +113,23 @@ any selection."
         ;; stop safe_run_hooks from clearing out pre-command-hook.
         (and (eq inhibit-quit 'pre-command-hook)
              (setq inhibit-quit 'delete-selection-dummy))
-        (signal 'file-supersession (cdr data)))))))
+        (signal 'file-supersession (cdr data)))
+       (text-read-only
+        ;; This signal may come either from `delete-active-region' or
+        ;; `self-insert-command' (when `overwrite-mode' is non-nil).
+        ;; To avoid clearing out `pre-command-hook' we handle this case
+        ;; by issuing a simple message.  Note, however, that we do not
+        ;; handle all related problems: When read-only text ends before
+        ;; the end of the region, the latter is not deleted but any
+        ;; subsequent insertion will succeed.  We could avoid this case
+        ;; by doing a (setq this-command 'ignore) here.  This would,
+        ;; however, still not handle the case where read-only text ends
+        ;; precisely where the region starts: In that case the deletion
+        ;; would succeed but the subsequent insertion would fail with a
+        ;; text-read-only error.  To handle that case we would have to
+        ;; investigate text properties at both ends of the region and
+        ;; skip the deletion when inserting text is forbidden there.
+        (message "Text is read-only") (ding))))))
 
 (put 'self-insert-command 'delete-selection t)
 (put 'self-insert-iso 'delete-selection t)
@@ -145,16 +163,21 @@ then it takes a second \\[keyboard-quit] to abort the minibuffer."
 (define-key minibuffer-local-must-match-map "\C-g" 'minibuffer-keyboard-quit)
 (define-key minibuffer-local-isearch-map "\C-g" 'minibuffer-keyboard-quit)
 
-(defun delsel-unload-hook ()
+(defun delsel-unload-function ()
+  "Unload the Delete Selection library."
   (define-key minibuffer-local-map "\C-g" 'abort-recursive-edit)
   (define-key minibuffer-local-ns-map "\C-g" 'abort-recursive-edit)
   (define-key minibuffer-local-completion-map "\C-g" 'abort-recursive-edit)
   (define-key minibuffer-local-must-match-map "\C-g" 'abort-recursive-edit)
-  (define-key minibuffer-local-isearch-map "\C-g" 'abort-recursive-edit))
-
-(add-hook 'delsel-unload-hook 'delsel-unload-hook)
+  (define-key minibuffer-local-isearch-map "\C-g" 'abort-recursive-edit)
+  (dolist (sym '(self-insert-command self-insert-iso yank clipboard-yank
+                insert-register delete-backward-char backward-delete-char-untabify
+                delete-char newline-and-indent newline open-line))
+    (put sym 'delete-selection nil))
+  ;; continue standard unloading
+  nil)
 
 (provide 'delsel)
 
-;;; arch-tag: 1e388890-1b50-4ed0-9347-763b1343b6ed
+;; arch-tag: 1e388890-1b50-4ed0-9347-763b1343b6ed
 ;;; delsel.el ends here