Re: [:upper:] inconsistency

[Stefan Monnier]

>> +        ;; Even if there's no uppercase char, we want to detect the use of
>> +        ;; [:upper:] char-class.

> Similarly, it would make sense for [:lower:] to disable case-folding.

Indeed.  And my previous patch was confused.  I believe the one below
should work.


        Stefan


--- orig/lisp/isearch.el
+++ mod/lisp/isearch.el
@@ -2297,7 +2297,17 @@
              (setq found t))
          (setq quote-flag nil)))
       (setq i (1+ i)))
-    (not found)))
+    (not (or found
+             ;; Even if there's no uppercase char, we want to detect the use
+             ;; of [:upper:] or [:lower:] char-class, which indicates
+             ;; clearly that the user cares about case distinction.
+             (and regexp-flag (string-match "\\[:\\(upp\\|low\\)er:]" string)
+                  (condition-case err
+                      (progn
+                        (string-match (substring string 0 (match-beginning 0)) 
"")
+                        nil)
+                    (invalid-regexp
+                     (equal "Unmatched [ or [^" (cadr err)))))))))
 
 ;; Portability functions to support various Emacs versions.