Next: , Up: current-kill   [Contents][Index]

The code for current-kill

The current-kill function is used by yank and by yank-pop. Here is the code for current-kill: 

(defun current-kill (n &optional do-not-move)
  "Rotate the yanking point by N places, and then return that kill.
If N is zero, `interprogram-paste-function' is set, and calling it
returns a string, then that string is added to the front of the
kill ring and returned as the latest kill.

If optional arg DO-NOT-MOVE is non-nil, then don't actually move the
yanking point; just return the Nth kill forward."
  (let ((interprogram-paste (and (= n 0)
                                 interprogram-paste-function
                                 (funcall interprogram-paste-function))))

    (if interprogram-paste
        (progn
          ;; Disable the interprogram cut function when we add the new
          ;; text to the kill ring, so Emacs doesn't try to own the
          ;; selection, with identical text.
          (let ((interprogram-cut-function nil))
            (kill-new interprogram-paste))
          interprogram-paste)

      (or kill-ring (error "Kill ring is empty"))
      (let ((ARGth-kill-element
             (nthcdr (mod (- n (length kill-ring-yank-pointer))
                          (length kill-ring))
                     kill-ring)))
        (or do-not-move
            (setq kill-ring-yank-pointer ARGth-kill-element))
        (car ARGth-kill-element)))))

Remember also that the kill-new function sets kill-ring-yank-pointer to the latest element of the kill ring, which means that all the functions that call it set the value indirectly: kill-append, copy-region-as-kill, kill-ring-save, kill-line, and kill-region.

Here is the line in kill-new, which is explained in The kill-new function. 

(setq kill-ring-yank-pointer kill-ring)