Re: [Emacs-diffs] /srv/bzr/emacs/trunk r108794: lisp/emacs-lisp/cl-lib.el (cl-pushnew): Don't capture X (bug#11811).

[Juanma Barranquero <lekktu@gmail.com>]

On Fri, Jun 29, 2012 at 6:42 PM, Stefan Monnier
<monnier@iro.umontreal.ca> wrote:
>> +       (let ((var (make-symbol "--cl-x--")))
>> +         `(let ((,var ,x))
>
> That's exactly what macroexp-let2 is for.

Something like this, you mean?

    Juanma


=== modified file 'lisp/emacs-lisp/cl-lib.el'
--- lisp/emacs-lisp/cl-lib.el	2012-06-28 23:04:27 +0000
+++ lisp/emacs-lisp/cl-lib.el	2012-06-29 16:53:17 +0000
@@ -151,16 +151,15 @@
                   [keywordp form])))
   (if (symbolp place)
       (if (null keys)
-	  (let ((var (make-symbol "--cl-x--")))
-	    `(let ((,var ,x))
-	       (if (memql ,var ,place)
+	  (macroexp-let2 nil var x
+	    `(if (memql ,var ,place)
 		   ;; This symbol may later on expand to actual code which then
 		   ;; trigger warnings like "value unused" since cl-pushnew's return
 		   ;; value is rarely used.  It should not matter that other
 		   ;; warnings may be silenced, since `place' is used earlier and
 		   ;; should have triggered them already.
 		   (with-no-warnings ,place)
-		 (setq ,place (cons ,var ,place)))))
+	       (setq ,place (cons ,var ,place))))
 	(list 'setq place (cl-list* 'cl-adjoin x place keys)))
     (cl-list* 'cl-callf2 'cl-adjoin x place keys)))