idea / showerthought / principle: try to standardize on C-o for invoking transient menus?

[dandrake]

I am loving the casual suite -- and the broader user interface approach with the transient menus in emacs -- and noticed that a number of them use C-o somehow to invoke the menu: re-builder, ibuffer, calc, bookmarks, and info.

That's what I have; it's possible your documentation for those doesn't always recommend C-o. But I guess the point of this issue is that it should! :)

Using a consistent keybinding improves usability -- it's easier to remember, more consistent, and more discoverable.

(In fact, while writing this issue, I used that discoverability -- I didn't recall the transient/casual menu binding for re-builder -- so I started it and just tried C-o. And there it was! Hooray!)

Your casual suite advertises itself as "opinionated" so I think it's fitting to have a strong opinion that C-o or variations thereof be the standard, easily-discoverable way to invoke these menus.

In fact, bigger picture, as others in the emacs blogosphere (is "blogosphere" still a thing in 2024?) have mentioned, I think this overall behavior / UI / workflow should be considered the standard approach for emacs going forward. There's the venerable C-h b and friends to see keybindings, but these menus are a very convenient and usable middle ground between:

1. Classic emacs functionality where you just need to know all the keybindings to do stuff in your buffer, and...
2. Classic emacs help functionality: C-h k, C-h w, C-h b, C-h m, info manuals, and so on.

So in my opinion, I think these casual/transient menus should be invoked with some kind of C-o keybinding whenever it makes sense. I know this isn't much of an issue, but I wanted to float the idea.

[kickingvegas]

Agreed. In fact, I recently changed the instructions for Casual I-Search to use the C-o binding. Going forward the convention for Casual packages is:

• If the main menu binding can be mode specific, use C-o.
  • Auxiliary menus such as sorting and search/filtering are bound best case wrt that mode’s bindings are for now.
    • Unclear to me at this point to unify sort binding which s for Dired and I-Buffer, S for Bookmarks.
• If the menu binding can be globally used and overrides a popular default binding (particularly a prefix), then try to best effort duplicate the same bindings that were replaced using that prefix. This is the example with Casual Avy using the binding M-g.

For those few folks that really like C-o bound to newline, my sympathies but the return key is always there.

[jdtsmith]

C-o isn't newline, but open-line, which is different in that it preserves point. There was a big debate on emacs-devel about C-o recently, and many came to its defense. M-o seems pretty good though.

[dandrake]

To be clear, I'd only want C-o where it's not already bound to something meaningful. So in a regular text buffer (or related), I would not overwrite C-o for open-line; rather, I'd want it in some prefix.

For modes re-builder, ibuffer, or elsewhere, using C-o in the base mode map works well.

And, in the end, I have no particular reason for C-o. Really I just want something consistent, easy, and discoverable. Thus far, C-o seems like a pretty decent candidate.

[kickingvegas]

@dandrake First let’s consider as axiomatic the ability for a user to always be able to choose their own binding to invoke a Casual menu. People are free to disregard the opinionated guidance I give. That said, here’s my take:

1. I think for most modes, a single, common ergonomic binding to invoke a Casual menu is desired.
2. Nearly all ergonomic bindings involving a modifier key in Emacs have been mapped to a command. It might be impossible to satisfy (1) without replacing an existing binding to a command.
3. I’ve stated clearly with Casual that I do not feel beholden to conform to existing Emacs mappings of bindings to commands.

Given the above, I’ve found C-o to personally satisfy the above for me, as I rarely use open-line. That said, I’m open to consider other binding candidates to suggest as the universal Casual key. Among them:

M-o
This suggestion by @jdtsmith is one that I find compelling as it is not commonly used in Emacs. My only concern is that for macOS, M-o is commonly used as the open command. On the other hand C-o is commonly used to open documents in Windows and Linux so it isn’t a strong concern.

F10
While this stomps over the existing binding to invoke a mouse-driven menu, for many F10 is unused because they rarely use the mouse menus. An objection to using function keys though would be its distance from the home row of a keyboard.

On the subject of open-line, I’ve been working on a library of Transient menus designed to help out with making some infrequently and frequently used commands related to editing text. This is not yet finalized but here’s a pre-release screenshot. Consider the scenario where this menu is invoked by C-o and if the user wanted to run open-line, could do so by typing C-o again.