[PATCH RFC v1] subr.el: add with-temp-indirect-buffer

[PATCH RFC v1] subr.el: add with-temp-indirect-buffer

[Lockywolf]

Add a macro to make a indirect clone of current buffer and run
some code in its context.
---
I would like to propose the following change, which implements a
macro called `with-temp-indirect-buffer', which can be useful
when writing automation codes which manipulate buffer view
properties, such as narrowing and widening.

lisp/subr.el | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/lisp/subr.el b/lisp/subr.el
index 2e2caf9fe27..1de0cb1d297 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -4890,6 +4890,25 @@ with-temp-buffer
            (and (buffer-name ,temp-buffer)
                 (kill-buffer ,temp-buffer)))))))
 
+(defmacro with-temp-indirect-buffer (&rest body)
+  "Create a temporary indirect buffer, and evaluate BODY there like `progn'.
+The buffer does not run the hooks `kill-buffer-hook',
+`kill-buffer-query-functions', and `buffer-list-update-hook'.
+See also `with-temp-file' and `with-output-to-string'."
+  (declare (indent 0) (debug t))
+  (let* ((temp-buffer (make-symbol "temp-indirect-buffer"))
+         (temp-buffer-name (generate-new-buffer-name (buffer-name))))
+    `(let ((,temp-buffer (clone-indirect-buffer ,temp-buffer-name nil t)))
+       ;; `kill-buffer' can change current-buffer in some odd cases.
+       ;; 2023-08-01: I have no idea what this means, so when writing
+       ;; this macro I just blindly copied the pattern from the
+       ;; with-temp-buffer
+       (with-current-buffer ,temp-buffer
+         (unwind-protect
+	     (progn ,@body)
+           (and (buffer-name ,temp-buffer)
+              (kill-buffer ,temp-buffer)))))))
+
 (defmacro with-silent-modifications (&rest body)
   "Execute BODY, pretending it does not modify the buffer.
 This macro is typically used around modifications of
-- 
2.35.8

Re: [PATCH RFC v1] subr.el: add with-temp-indirect-buffer

[Eli Zaretskii]

> From: Lockywolf <for_emacs.clonebuffer_2023-08-01@lockywolf.net>
> Cc: Lockywolf <for_emacs.clonebuffer_2023-08-01@lockywolf.net>
> Date: Tue,  1 Aug 2023 12:28:13 +0800
> 
> Add a macro to make a indirect clone of current buffer and run
> some code in its context.

Does anyone think we need this macro in Emacs?  Did people frequently
had to invent something like that?

If this is an infrequent need, I'd rather leave this to Lisp programs
that need it.

Thanks.