Subject: Re: bug#6984: rx generates wrong regular expression for class
From: Stefan Monnier <[email-masked]>
To: Daniel Colascione <[email-masked]>
Date: Sun, 05 Sep 2010 11:44:42 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

>>>>> "Daniel" == Daniel Colascione <[email-masked]> writes:

> (rx (in (?0 . ?3) ?, ?-))
> generates

> "[,-0-3]"

Thanks.  I've just installed the patch below in the emacs-23 branch,
which should fix it (in two different ways).

        Stefan

=== modified file 'lisp/emacs-lisp/rx.el'
--- lisp/emacs-lisp/rx.el	2010-06-29 12:09:07 +0000
+++ lisp/emacs-lisp/rx.el	2010-09-05 09:37:06 +0000
@@ -427,7 +427,7 @@
 	    (mapcar (lambda (e)
 		      (cond
 		       ((= (car e) (cdr e)) (list (car e)))
-		       ;; ((= (1+ (car e)) (cdr e)) (list (car e) (cdr e)))
+		       ((= (1+ (car e)) (cdr e)) (list (car e) (cdr e)))
 		       ((list e))))
 		    l))
      (delete-dups str))))
@@ -545,7 +545,10 @@
 			    ((numberp e) (string e))
 			    ((consp e)
 			     (if (and (= (1+ (car e)) (cdr e))
-				      (null (memq (car e) '(?\] ?-))))
+                                      ;; rx-any-condense-range should
+                                      ;; prevent this case from happening.
+				      (null (memq (car e) '(?\] ?-)))
+                                      (null (memq (cdr e) '(?\] ?-))))
 				 (string (car e) (cdr e))
 			       (string (car e) ?- (cdr e))))
 			    (e)))