Provide generalized variables in core Elisp.

* lisp/emacs-lisp/gv.el: New file.
* lisp/subr.el (push, pop): Extend to generalized variables.
* lisp/loadup.el (macroexp): Unload if preloaded and uncompiled.
* lisp/emacs-lisp/cl-lib.el (cl-pop, cl-push, cl--set-nthcdr): Remove.
* lisp/emacs-lisp/cl-macs.el: Require gv.  Use gv-define-setter,
gv-define-simple-setter, and gv-define-expander.
Remove setf-methods defined in gv.  Rename cl-setf -> setf.
(cl-setf, cl-do-pop, cl-get-setf-method): Remove.
(cl-letf, cl-letf*, cl-define-modify-macro, cl-defsetf)
(cl-define-setf-expander, cl-struct-setf-expander): Move to cl.el.
(cl-remf, cl-shiftf, cl-rotatef, cl-callf, cl-callf2): Rewrite with
gv-letplace.
(cl-defstruct): Don't define setf-method any more.
* lisp/emacs-lisp/cl.el (flet): Don't autoload.
(cl--letf, letf, cl--letf*, letf*, cl--gv-adapt)
(define-setf-expander, defsetf, define-modify-macro)
(cl-struct-setf-expander): Move from cl-lib.el.
* lisp/emacs-lisp/syntax.el:
* lisp/emacs-lisp/ewoc.el:
* lisp/emacs-lisp/smie.el:
* lisp/emacs-lisp/cconv.el:
* lisp/emacs-lisp/timer.el: Rename cl-setf -> setf, cl-push -> push.
(timer--time): Use gv-define-simple-setter.
* lisp/emacs-lisp/macroexp.el (macroexp-let2): Rename from macroexp-let²
to avoid coding-system problems in subr.el.  Adjust all users.
(macroexp--maxsize, macroexp-small-p): New functions.
* lisp/emacs-lisp/bytecomp.el (byte-compile-file): Don't use cl-letf.
* lisp/scroll-bar.el (scroll-bar-mode):
* lisp/simple.el (auto-fill-mode, overwrite-mode, binary-overwrite-mode)
(normal-erase-is-backspace-mode): Don't use the `eq' place.
* lisp/winner.el (winner-configuration, winner-make-point-alist)
(winner-set-conf, winner-get-point, winner-set): Don't abuse letf.
* lisp/files.el (locate-file-completion-table): Avoid list*.

Fixes: debbugs:11657

1 files changed, 11 insertions, 5 deletions

diff --git a/lisp/simple.el b/lisp/simple.el
index 655298e4fea..5d56a64eb23 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -5425,7 +5425,9 @@ non-`nil'.
 
 The value of `normal-auto-fill-function' specifies the function to use
 for `auto-fill-function' when turning Auto Fill mode on."
-  :variable (eq auto-fill-function normal-auto-fill-function))
+  :variable (auto-fill-function
+             . (lambda (v) (setq auto-fill-function
+                            (if v normal-auto-fill-function)))))
 
 ;; This holds a document string used to document auto-fill-mode.
 (defun auto-fill-function ()
@@ -5538,7 +5540,8 @@ the line.  Before a tab, such characters insert until the tab is
 filled in.  \\[quoted-insert] still inserts characters in
 overwrite mode; this is supposed to make it easier to insert
 characters when necessary."
-  :variable (eq overwrite-mode 'overwrite-mode-textual))
+  :variable (overwrite-mode
+             . (lambda (v) (setq overwrite-mode (if v 'overwrite-mode-textual)))))
 
 (define-minor-mode binary-overwrite-mode
   "Toggle Binary Overwrite mode.
@@ -5557,7 +5560,8 @@ ordinary typing characters do.
 Note that Binary Overwrite mode is not its own minor mode; it is
 a specialization of overwrite mode, entered by setting the
 `overwrite-mode' variable to `overwrite-mode-binary'."
-  :variable (eq overwrite-mode 'overwrite-mode-binary))
+  :variable (overwrite-mode
+             . (lambda (v) (setq overwrite-mode (if v 'overwrite-mode-binary)))))
 
 (define-minor-mode line-number-mode
   "Toggle line number display in the mode line (Line Number mode).
@@ -6780,8 +6784,10 @@ 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'."
-  :variable (eq (terminal-parameter
-                 nil 'normal-erase-is-backspace) 1)
+  :variable ((eq (terminal-parameter nil 'normal-erase-is-backspace) 1)
+             . (lambda (v)
+                 (setf (terminal-parameter nil 'normal-erase-is-backspace)
+                       (if v 1 0))))
   (let ((enabled (eq 1 (terminal-parameter
                         nil 'normal-erase-is-backspace))))