bug#46621: Copy line

[Helmut Eller]

> With a single keybinding, you can duplicate once, visually confirm
> that this is what you want to do, and keep duplicating (possibly even
> holding the key down to repeat!) until you have the number of copies
> you want. If you go too far, just undo. In other words, it behaves
> just like any basic text-editing feature. And all of this is
> available, with exactly the same key, for regions and rectangles!
>
> None of that is possible with a multi-key binding. If you made too
> many copies you have to erase them by hand, or undo and restart the
> process with a new prefix number. All of this adds cognitive load, and
> each attempt requires a series of keypresses.

For this use case 'repeat' seems quite usable:

  M-x copy-line C-x z z z z z

or whatever number of zs you need.

Helmut