一个`query-replace`，它要求每次出现一个新的替换字符串

Question

I'm looking for a function which works similar as query-replace but instead of using the same replacement string over and over again, asks for a replacement string each time a match is found. That is to say, once a match is found, you can either skip this match or enter replacement mode, where you can specify which string is to be used for replacing the match (with a history of previous replacements).

Even more useful would be the query-replace-regexp variant, which allows to use the groupings of the search string.

I have written some piece of code to be used for the non-regexp version, however, I'm stuck at the part of actually replacing something and repeating the whole search after a replacement was done/the match was skipped. The code so far is:

(defun query-replace-ask (search)
  (interactive "sQuery replace: ")
  (if (search-forward search nil t)
      (let ((beg (match-beginning 0))
            (end (match-end 0))
            (if (y-or-n-p "Replace?")
                (replacement (read-string "Replacement: "))
              (
               ;; Do the next search
               )))
        ;; Replace from beg to end with replacement
        ;; do the next search
        )))

Also, it would be nice if the function could output the number of total replacements once the function finishes.

Answer 1

This functionality is already part of query-replace . You can call it with E . To see all options, press ? while replacing.

Answer 2

For query-replace-regexp , you may want to use \\? in the replacement string. It will ask for input at every occurrence that you decide to act on, and you may combine it with other regexp features such as groupings and elisp ( \\, ). This is described in this manual page .

Answer 3

Yes, the answer for query-replace is e (or E ).

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But you might also be interested in an alternative: search with replacement on demand .

In Icicles you can access search hits in any order -- visit (or revisit) just the ones you're interested in. You can see some surrounding context for choosing hits, without having to visit them. You can visit some of them individually or cycle among some or all of them, in various cycle orders.

When you visit an occurrence you can hit a key to tell Icicles you want to replace text in the match, and if so whether to prompt you for new replacement text.

IOW, replacement is on demand. You need not visit all hits in a particular order (occurrence in buffer) and you are not obliged to indicate for each hit what to do (skip/replace/edit etc.).

Go directly to the matches you are interested in, and perform replacement when it is appropriate. You tell Emacs what you want; it does not ask you "Do you want this one? this one? this one? this one?...)"

Just mentioning this as an alternative that can be powerful for some uses. It is not a replacement for query-replace for all uses.

http://www.emacswiki.org/emacs/Icicles_-_Search_Commands%2c_Overview

Answer 4

Isearch+ now offers a similar on-demand replacing feature to that provided by Icicles .

When you visit any search hit you can use Cu CM-RET to be prompted for replacement text. (Without the prefix arg, the last replacement text is reused.)

Replacement can also use the special regexp constructs allowed for query-replace-regexp : \\& , \\=\\N', # , \\, and \\?`.

For example, suppose you use a regexp-search pattern of \\(e\\)\\|a and a replacement pattern of \\,(if \\1 "a" "e") . Each CM-RET will then swap e for a and vice versa.