Re: replace history

[Juri Linkov <juri@jurta.org>]

> In Emacs 22 it's great the way that you are given the last search/replace
> pair as a default for query-replace, but is there a way to get a history
> of pairs rather than alternating search item/replace item?

One way to implement this feature is to use one input string with the
ed-like syntax "s/regex/substitution/g".

Below is the simplest function that implements this.  It reads such
a string from the minibuffer (with the query-replace history list and
a convenient default input string), parses it and calls perform-replace
with proper arguments querying for each replacement when the input string
contains the "g" flag.

(defun substitute-regexp (substitution)
  (interactive
   (list
    (read-from-minibuffer "Substitute regexp: " '("s///g" . 3) nil nil
                          'query-replace-history nil t)))
  (if (string-match "^s/\\(.*\\)/\\(.*\\)/\\([gi]*\\)" substitution)
      (let* ((regex (match-string 1 substitution))
             (subst (match-string 2 substitution))
             (flags (match-string 3 substitution))
             (case-fold-search (string-match "i" flags)))
        (perform-replace
         regex subst (string-match "g" flags)
         t nil nil nil
         (if (and transient-mark-mode mark-active) (region-beginning))
         (if (and transient-mark-mode mark-active) (region-end))))
    (error "Invalid syntax")))

-- 
Juri Linkov
http://www.jurta.org/emacs/