bug#52245: Wishlist: cycle input methods

[John Ankarström]

Eli Zaretskii <eliz@gnu.org> writes:

> The use case that I have in mind is this: even if the user customized
> the list of input methods to include more than just one, there could
> be situations where the user needs to use just one input method when
> typing.  In such situations, it would be good to have a way of
> toggling, like we do now, instead of cycling through all the other
> methods.
>
> Any reasonable solution to this use case would be welcome.  I'm
> working with systems which allow you to do something like that, and it
> frequently annoys me to have to cycle through all the keyboard layouts
> I defined, just to be able to toggle between US English and some other
> language.  So I wish that Emacs didn't have such an annoying problem,
> if possible.

IIRC Windows 10 handles this by implementing the input method list as a
stack of sorts, so that Win-Space selects an input method similarly to
how Alt-Tab selects a window. Pressing Win-Space once is a toggle, but
pressing Win-Space consecutively (while holding Win) cycles through all
input methods.

Emacs could do something similar. A single C-\ could toggle between the
two input methods at the top of the list, whereas any number of
consecutive C-\'s could cycle the list. The implementation would just
need to check last-command.