Re: Want to delete distinct regions but make capable undo by single command.

[Oleksandr Gavenko <gavenkoa@gmail.com>]

Oleksandr Gavenko <gavenkoa <at> gmail.com> writes:

> 
> Want to delete distinct regions but make capable undo by single command
> (programmatically).
> 
> Like this happen after automatic replacement ('!'). You undo by 'M-_' all
> replacement at once instead sequentially each individually.
> 

Wrote such code:

(defun my-org-kill-by-tag (tag)
  "Put all entries that matches TAG from current org-file to `kill-ring'."
  (interactive (list (completing-read "Enter tag: " (org-get-buffer-tags))))
  (kill-new "")
  (org-scan-tags
   (lambda ()
     (let ( (last-command 'kill-region) )
       (org-cut-subtree)))
   '(member tag tags-list)
   nil) )

See origin:

  http://thread.gmane.org/gmane.emacs.orgmode/71263
            Kill all items with specific tag to kill-ring.

which exploit 'org-cut-subtree' implementation with:

  (let ( (last-command 'kill-region) ) ...kill-commands...)

To make this possible your code MUST use only high-level kill ring
functions. Which take care on "last-command == kill-region".

If some function in code use 'kill-new' or 'kill-append' - 'last-command'
trick fail...