bug#52417: Mark ring navigation could be two-way

[Daniel Martín]

ndame via "Bug reports for GNU Emacs, the Swiss army knife of text
editors" <bug-gnu-emacs@gnu.org> writes:

> Other tools has similar features like the mark ring and they
> provide two-way navigation, so you can go back to some previous
> position to check something, and then you can go forward in the
> ring to get back to a more recent position or the latest position
> if you want.
>
> Emacs could have this too by providing a command which allows
> moving forward in the mark ring.

+1.  I agree that this is a useful feature that would improve the text
editing capabilities of Emacs.  In Vim, you can use C-i and C-o to
navigate forwards and backwards, respectively.

A similar thing happens with the kill-ring.  M-y moves the last-yank
pointer in one direction, but there could be a command to move it in the
opposite direction.  Even if the mark and kill ring cycle, it is
inconvenient to browse them in one direction only, because as modern
computers have more memory available, the rings can store more things.

This is probably one of the reasons why there are a lot of external
packages that let you browse the contents of the mark-ring and kill-ring
in the minibuffer or a separate buffer.