Re: regexp repacement, how to present replacement to user?

[David Kastrup <dak@gnu.org>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> (let ((from "\\([[:alpha:]]+\\)-\\([[:alpha:]]+\\)")
>>       (to "\\1 \\2"))
>>   (while (re-search-forward from nil t)
>>     (if (y-or-n-p (format "Replace %s with %s "
>>                           (match-string 0)
>>                           (replace-regexp-in-string from to (match-string 0))))
>>         (replace-match to nil nil))))
>
> This work 99% with the last 1% being due to failure in boundary conditions
> (e.g. if the pattern starts with "\\>").

     (while (re-search-forward from nil t)
        (if y-or-n-p (format "Replace %s with %s "
                       (match-string 0)
                          (save-match-data
                            (replace-match to nil nil (match-string 0)
                             (prog1 nil
                               (set-match-data
                                 (mapcar
                                   (lambda(x)(if (numberp x)
                                                   (- x (match-beginning 0))
                                                   x)))
                                 (match-data t)))

[...]

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum