How can I replace all in symbol manner?

Question

I am using following solution (How do I add a keybinding to use during an interactive isearch, `C-s ...`) to move over symbols in the buffer, which iterates over the matching symbols:

(define-key isearch-mode-map (kbd "C-w")
  'isearch-forward-symbol-at-point)

Is it possible to apply same manner into replace-all where instead of text it replaces the symbols (where the isearch-forward-symbol-at-point iterates over):

My query replace function, which replace all the matching query instead of only the symbols:

(defun query-replace-region-or-from-top ()
  (interactive)
  (let ((case-fold-search nil))
    (progn
      (let ((orig-point (point)))
        (if (use-region-p)
            (call-interactively 'query-replace)
          (save-excursion
            (goto-char (point-min))
            (call-interactively 'query-replace)))
        (message "Back to old point.")
        (goto-char orig-point)))))
(global-set-key "\C-x\C-r"  'query-replace-region-or-from-top)

---

Example_1:

gas_costs = 100
_cost = 10
log(f"==> cost={_cost}")

Replace-all _cost into cost

=> changes into:

gascosts = 100
cost = 10
log(f"==> cost={cost}")

wanted:

gas_cost = 100  # should remain unchanged
cost = 100
log(f"==> cost={cost}")

---

Example_2:

alper = 100
alper99 = 99

Replace-all alper into sad

=> changes into:

sad = 100
sad99 = 99

wanted:

sad = 100
alper99 = 99

---

I just want to replace patterns as exactly same with isearch finds. Because first I always search patterns using isearch and than replace them. But if there are diffierent matched patterns in replace-all, I get end up replacing differect results than isearch finds.

Answer 1

EDIT in response to the question in your comment

To use the regexp pattern as a default in your function, you could use the following code (note that here I have also somewhat improved the regexp and replace patterns):

(defun query-replace-region-or-from-top (pattern &optional beg end)
  (interactive "sEnter symbol: \nr")
  (let ((case-fold-search nil)
        (regexp (concat "\\([[:blank:]{]\\|^\\)" pattern)))
    (save-excursion
      (goto-char (point-min))
      (apply #'query-replace-regexp
             regexp
             (concat "\\1" (substring pattern 1))
             nil
             (when (use-region-p)
               (list beg end))))))

Note that I have also added the default replace pattern, which is the pattern minus the starting _. If you don't want that, then you could ask for a second string in the interactive form, and use that for the replacement pattern. Or you could only ask for the replacement pattern and automatically 'compose' the regexp pattern. Of course, I don't know your exact use case(s).

END EDIT

From your explanation, it is not clear to me what you are asking exactly (e.g. what is replace-all). But it looks to me that the answer to your 'main' question is that you are actually looking for (query-)replace-regexp.

E.g. to solve the problem of your example, you can use query-replace-regexp using the following regexp \([[:space:]{]\|^\)+_cost (and replace with cost).

Some comments about your function:

• the progn is redundant, as you are already within a let (and so the second let is also redundant).
• you are setting the orig-point and jump back to it, while you are also using save-excursion within. So to me, the save-excursion looks ineffective. To get the same effect, you can just wrap the whole if in save-excursion.

However, maybe you want something like the following:

(defun query-replace-region-or-from-top (&optional mark)
  (interactive "m")
  (let ((case-fold-search nil))
    (cond ((use-region-p)
           (call-interactively 'query-replace-regexp)
           (goto-char (min region)))
          (t
           (save-excursion
             (goto-char (point-min))
             (call-interactively 'query-replace-regexp))))))

You could alternatively use the interactive code r, if you would like to jump back to either the beginning or the end of your region.