Re: vertical fido-mode

[Juri Linkov]

> While in the minibuffer the horizontal arrows are used to
> move-forward/backward and the vertical to search in history.
>
> Do you have any alternative?

An alternative would be to use the same keys as used in web browsers
to navigate completions from the url input field where M-up and M-down
are used to display a list of completions and to navigate in completions,
without switching to the completions buffer.

> OTOH this is the simplest I could implement making minimal changes with
> the hope of making some of this enabled by default in the "near" future
> without too many old users complains.
>
> Otherwise we will implement just-another new mode that will be off by
> default and probably nobody will use as there is ido/fido/icomplete/ivy
> and so on.
>
> So far there are some details in the actual user experience with
> *Completes* I didn't change intentionally.
>
> 1) Completions are only shown on demand (TAB)
>
> 2) When completions are shown TAB tries to scroll the completions buffer
> if not all of them are visible (actual behavior)

There are other keys that currently scroll the completions buffer as well:
M-PgUp, M-PgDown, M-C-v, S-M-C-v.

> 3) The completions are updated on demand (TAB) only (unlike zsh that they are
> updated automatically on input)

I think whether to show/update completions only on demand or to show/update
them automatically on input should be customizable with a new option.

> 4) Arrows and navigation keys keep their current meaning either in
> minibuffer and *Completions* buffer.
>
> So far this doesn't changes the current experience at all, so old users
> won't complain and we could enable this by default.

I agree that any changes in the default behavior should be unobtrusive.

> The only addition was the jump to completions with a TAB when all
> completions are shown.

The existing key that already jumps to completions is PgUp (M-v).

> And exit completions with C-g like in zsh.

The existing key to exit completions is ESC (delete-completion-window).

> Do you think it worth doing a stronger change?

I think that adding more logic to the existing key TAB is too strong
change: for example, when the user doesn't notice that the completions
buffer already displays all completions, types TAB again, and it switches
to the completions buffer contrary to user wishes.

OTOH, the feature of using TAB to switch to the completions buffer
doesn't work when the list of completions is too big and
not all completions are displayed.