Re: `insert' deactivates active region

[Masatake YAMATO]

Yamaoka-san, could you try this code?

(let ((buffer (get-buffer-create "*testing*")))
  (pop-to-buffer buffer)
  (erase-buffer)
  (insert "Hello World\n")
  (goto-char (point-min))
  (set (make-local-variable 'transient-mark-mode) t)
  (add-hook 'post-command-hook
            (lambda nil
              (with-temp-buffer
                (insert "foo")
                (setq deactivate-mark nil)
                ))
            nil t))

or 

(let ((buffer (get-buffer-create "*testing*")))
  (pop-to-buffer buffer)
  (erase-buffer)
  (insert "Hello World\n")
  (goto-char (point-min))
  (set (make-local-variable 'transient-mark-mode) t)
  (add-hook 'post-command-hook
            (lambda nil
              (with-temp-buffer
                (let (deactivate-mark)
                  (insert "foo"))
                ))
            nil t))

If you think this work-around is not enough, talk to emacs-devel.
I'll write a report my investigation about this bug.

Masatake YAMATO