(normal-erase-is-backspace): Rename from

delete-key-deletes-forward.  Doc fix.
(normal-erase-is-backspace-mode): Rename from
delete-key-deletes-forward-mode.  Doc fix.  Run
normal-erase-is-backspace-hook.

2 files changed, 58 insertions, 20 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 8bfbd354d79..d2671d2458a 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,17 @@
 2001-04-04  Eli Zaretskii  <eliz@is.elta.co.il>
 
+        * cus-load.el (normal-erase-is-backspace): Use it instead of
+        delete-key-deletes-forward.
+
+        * startup.el (command-line): Use normal-erase-is-backspace and
+        normal-erase-is-backspace-mode.
+
+        * simple.el (normal-erase-is-backspace): Rename from
+        delete-key-deletes-forward.  Doc fix.
+        (normal-erase-is-backspace-mode): Rename from
+        delete-key-deletes-forward-mode.  Doc fix.  Run
+        normal-erase-is-backspace-hook.
+
         * dired.el (dired-move-to-filename-regexp): Support file sizes in
         ``human-readable'' format produced by GNU `ls'.  
         (dired-move-to-filename-regexp): Recognize ISO format dates.  From
diff --git a/lisp/simple.el b/lisp/simple.el
index e4f5108c356..6f270128ce1 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -4044,16 +4044,16 @@ DESCRIPTION is the descriptive string for the syntax.")
 
 ;;; Handling of Backspace and Delete keys.
 
-(defcustom delete-key-deletes-forward nil
-  "Whether the Delete key should delete forward or not.
+(defcustom normal-erase-is-backspace nil
+  "If non-nil, Delete key deletes forward and Backspace key deletes backward.
 
 On window systems, the default value of this option is chosen
 according to the keyboard used.  If the keyboard has both a Backspace
 key and a Delete key, and both are mapped to their usual meanings, the
 option's default value is set to t, so that Backspace can be used to
-delete backward, and Delete can be used used to delete forward
+delete backward, and Delete can be used to delete forward.
 
-If not running under a window system, setting this option accomplishes
+If not running under a window system, customizing this option accomplishes
 a similar effect by mapping C-h, which is usually generated by the
 Backspace key, to DEL, and by mapping DEL to C-d via
 `keyboard-translate'.  The former functionality of C-h is available on
@@ -4061,31 +4061,57 @@ the F1 key.  You should probably not use this setting if you don't
 have both Backspace, Delete and F1 keys.
 
 Setting this variable with setq doesn't take effect.  Programmatically,
-call `delete-key-deleted-forward-mode' instead."
+call `normal-erase-is-backspace-mode' (which see) instead."
   :type 'boolean
   :group 'editing-basics
   :version "21.1"
   :set (lambda (symbol value)
          ;; The fboundp is because of a problem with :set when
          ;; dumping Emacs.  It doesn't really matter.
-         (if (fboundp 'delete-key-deletes-forward-mode)
-             (delete-key-deletes-forward-mode (or value 0))
+         (if (fboundp 'normal-erase-is-backspace-mode)
+             (normal-erase-is-backspace-mode (or value 0))
            (set-default symbol value))))
 
 
-(defun delete-key-deletes-forward-mode (&optional arg)
-  "Toggle Delete key deleting forward or backward.
-With numeric arg, turn the mode on if and only iff ARG is positive.
-For more details, see `delete-key-deletes-forward'."
+(defun normal-erase-is-backspace-mode (&optional arg)
+  "Toggle the Erase and Delete mode of the Backspace and Delete keys.
+
+With numeric arg, turn the mode on if and only ARG is positive.
+
+On window systems, when this mode is on, Delete is mapped to C-d and
+Backspace is mapped to DEL; when this mode is off, both Delete and
+Backspace are mapped to DEL.  (The remapping goes via
+`function-key-map', so binding Delete or Backspace in the global or
+local keymap will override that.)
+
+In addition, on window systems, the bindings of C-Delete, M-Delete,
+C-M-Delete, C-Backspace, M-Backspace, and C-M-Backspace are changed in
+the global keymap in accordance with the functionality of Delete and
+Backspace.  For example, if Delete is remapped to C-d, which deletes
+forward, C-Delete is bound to `kill-word', but if Delete is remapped
+to DEL, which deletes backward, C-Delete is bound to
+`backward-kill-word'.
+
+If not running on a window system, a similar effect is accomplished by
+remapping C-h (normally produced by the Backspace key) and DEL via
+`keyboard-translate': if this mode is on, C-h is mapped to DEL and DEL
+to C-d; if it's off, the keys are not remapped.
+
+When not running on a window system, and this mode is turned on, the
+former functionality of C-h is available on the F1 key.  You should
+probably not turn on this mode on a text-only terminal if you don't
+have both Backspace, Delete and F1 keys.
+
+See also `normal-erase-is-backspace'."
   (interactive "P")
-  (setq delete-key-deletes-forward
+  (setq normal-erase-is-backspace
         (if arg
             (> (prefix-numeric-value arg) 0)
-          (not delete-key-deletes-forward)))
+          (not normal-erase-is-backspace)))
 
   (cond ((or (memq window-system '(x w32 mac pc))
              (memq system-type '(ms-dos windows-nt)))
-         (let ((bindings 
+         (let ((bindings
                 `(([C-delete] [C-backspace])
                   ([M-delete] [M-backspace])
                   ([C-M-delete] [C-M-backspace])
@@ -4093,7 +4119,7 @@ For more details, see `delete-key-deletes-forward'."
                    [C-delete] [C-backspace])))
                (old-state (lookup-key function-key-map [delete])))
 
-           (if delete-key-deletes-forward
+           (if normal-erase-is-backspace
                (progn
                  (define-key function-key-map [delete] [?\C-d])
                  (define-key function-key-map [kp-delete] [?\C-d])
@@ -4115,19 +4141,19 @@ For more details, see `delete-key-deletes-forward'."
                    (define-key map key1 binding2)
                    (define-key map key2 binding1)))))))
          (t
-          (if delete-key-deletes-forward
+          (if normal-erase-is-backspace
               (progn
                 (keyboard-translate ?\C-h ?\C-?)
                 (keyboard-translate ?\C-? ?\C-d))
             (keyboard-translate ?\C-h ?\C-h)
             (keyboard-translate ?\C-? ?\C-?))))
 
-  (run-hooks 'delete-key-deletes-forward-hook)
+  (run-hooks 'normal-erase-is-backspace-hook)
   (if (interactive-p)
-      (message "Delete key deletes %s" 
-               (if delete-key-deletes-forward "forward" "backward"))))
+      (message "Delete key deletes %s"
+               (if normal-erase-is-backspace "forward" "backward"))))
+
 
-  
 ;;; Misc
 
 (defun byte-compiling-files-p ()