Re: regexp case sensitivity bug

[Richard Stallman]

    Or we can use a completely different approach:

    (defun isearch-no-upper-case-p (string regexp-flag)
      "..."
      (let ((case-fold-search nil))
        (save-match-data
          (null (string-match 
                  (if regexp-flag "\\(^\\|[^\\]\\)[[:upper:]]" "[[:upper:]]")
                  string)))))

That's not correct in the case where there are two \'s in a row
(or any even number).