bug#52558: Option for easier typing of regexps

[Juri Linkov]

>>> Such option already exists, and it allows using custom regexp syntax
>>> both for isearch and query-replace:
>>
>> Interesting, though its help mentions only isearch, so if I start
>> M-x query-replace-regexp directly, it doesn't seem affected.
>
> If you want to use M-x query-replace directly,
> then simpler would be add replace-regexp-function
> that you can use with:
>
> (setq replace-regexp-function

And additional change is needed for correct highlighting:

diff --git a/lisp/replace.el b/lisp/replace.el
index 0e81b15a09..4302868520 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -2690,7 +2693,8 @@ replace-highlight
   (if query-replace-lazy-highlight
       (let ((isearch-string search-string)
            (isearch-regexp regexp-flag)
-           (isearch-regexp-function (or delimited-flag
+           (isearch-regexp-function (or replace-regexp-function
+                                         delimited-flag
                                         (and replace-char-fold
                                              (not regexp-flag)
                                              #'char-fold-to-regexp)))