Once you have an item in the kill ring, you can paste it back into a buffer as many times as you like.
Ctrl+Yto paste the text in the kill ring back into the buffer.
With many editors you can only do this with one item at a time. The clipboard is only able to contain one item, and so it is the only one available for pasting back into the text.
However, the kill ring allows you to keep many items. Any of these items can be pasted back into your document at any time. Every time you cut or copy something, it is added to the kill ring, so you accumulate more items in the kill ring as your session progresses.
Consider the following example. In Kill ring with three items, the kill ring contains three items; the words
Figure 13.12 Kill ring with three items
First, the word
was cut from the current buffer (this would remove it from the buffer). Next, the word
was copied (which would leave it in the buffer but add a copy of it to the kill ring), and lastly, the word
Note the concept of the kill ring rotating (this is why it is known as a ring). Every time a new item is added (at the top, in these figures), the others are all shunted around in a counter-clockwise direction.
Whenever you perform a paste, the current item in the kill ring--the word
in this case--is copied back into the buffer wherever the cursor currently is.
Note that the current item is not removed from the kill ring.
Figure 13.13 Pasting from the kill ring
What you have seen so far does exactly the same thing as the standard clipboard. True, all three items have been kept in the kill ring, but they are of no use if you cannot actually get at them.
The Emacs key to do this is
. This rotates the kill ring in the opposite direction--thus making the previous item the current one--and pastes it into the buffer in place of the item just pasted. In Pasting from the kill ring, the word
would be replaced with the word
You can use
as many times as you like. For instance, if you actually wanted to paste the word
in the document, pressing
would replace the word
with the word
Figure 13.14 Rotating the kill ring
If you pressed
a third time, the kill ring would have rotated completely, and
would have been the current item once again.
You can never use
without having used
Here is a summary of the way
Ctrl+Ypastes the current item in the kill ring into the buffer.
Alt+Yrotates the kill ring back one place, and then pastes the current item into the buffer, replacing the previously pasted item.