Modalka

What is this?
- What Modalka is not
- Why should I use it then?
Installation
Example of use
Usage
Customization
Other solutions
- Evil
- Control Mode
- God Mode
- Boon
- Fingers
- Xah Fly Keys
- Ergoemacs Mode
License

What is this?

This is a building kit to help switch to modal editing in Emacs.

In this article I use Vi-inspired terms when I refer to the modes of operation:

In the normal mode you manipulate existing text and keystrokes typically result in editing operations instead of insertion of characters.
In the insert mode keystrokes insert the corresponding characters, i.e. it's how Emacs works by default.

What Modalka is not

Modalka does not introduce a new keyboard layout for the normal mode, you set it up yourself.
Modalka does not provide new commands for editing.

Why should I use it then?

Modal editing is more efficient, but most importantly, it is better for health. This package allows its users to switch from tiring Ctrl-based key combinations to editing through normal typing. The transition can be gradual and the user can define their own layout.

Installation

The package is available via MELPA, so you can just type M-x package-install RET modalka RET.

If you would like to install the package manually, download or clone it and put on Emacs' load-path. Then you can require it in your init file like this:

(require 'modalka)

Example of use

Here is a simple collection of translations that an Emacs user could easily adopt:

(modalka-define-kbd "W" "M-w")
(modalka-define-kbd "Y" "M-y")
(modalka-define-kbd "a" "C-a")
(modalka-define-kbd "b" "C-b")
(modalka-define-kbd "e" "C-e")
(modalka-define-kbd "f" "C-f")
(modalka-define-kbd "g" "C-g")
(modalka-define-kbd "n" "C-n")
(modalka-define-kbd "p" "C-p")
(modalka-define-kbd "w" "C-w")
(modalka-define-kbd "y" "C-y")
(modalka-define-kbd "SPC" "C-SPC")

One can type M-x modalka-mode to try it. When in the normal mode (modalka-mode) with such a setup, two lines of text can be killed like this: SPC n n w. Note that Modalka can translate sequential key bindings such as x ;, too.

Numeric prefixes can also be added:

(modalka-define-kbd "2" "C-2")

Now twenty-two lines can be killed with SPC 2 2 n w.

For an example of a complete setup see this.

Usage

Modalka is implemented as a minor mode called modalka-mode. This section describes how to set up efficient modal editing and provides some tips.

How to define translations

There is a set of functions to define key translations and to remove them:

modalka-define-key
modalka-remove-key

Here are the versions that wrap their arguments with kbd:

modalka-define-kbd
modalka-remove-kbd

Using these functions it's easy to setup a translation map.

Note that the target key binding cannot be a prefix key:

(modalka-define-kbd "x" "C-x") ;; will not work

Translations involving prefix keys will be ignored.

If you want to bind a command in modalka-mode without performing a keybinding translation, remember that modalka-mode is just a normal minor mode which has an associated key map called modalka-mode-map. So you can do the following:

(define-key modalka-mode-map (kbd "Q") #'my-command)

Using this approach it is possible to remap a prefix key like this:

(define-key modalka-mode-map "x" ctl-x-map)
(define-key ctl-x-map (kbd "e") #'eval-last-sexp)
(define-key ctl-x-map (kbd "s") #'save-buffer)

How to activate the minor mode

One should bind a key to toggle modalka-mode. This should be an easy key— one keystroke, easy to reach. I would even advise binding ; or Enter:

(global-set-key (kbd "<return>") #'modalka-mode)

The next thing to decide is whether modalka-mode should be enabled by default. modalka-mode can be enabled everywhere (except for the minibuffer) by activating modalka-global-mode:

(modalka-global-mode 1)

It is also possible to give Modalka a list of major modes where it should not be enabled:

(add-to-list 'modalka-excluded-modes 'magit-status-mode)

However, one may choose to enable modalka-mode only in conjunction with certain major modes:

(add-hook 'text-mode-hook #'modalka-mode)
(add-hook 'prog-mode-hook #'modalka-mode)

This is a whitelisting approach. modalka-global-mode and modalka-excluded-modes implement a blacklisting approach.

Change the cursor shape for visual feedback

modalka-mode comes with a lighter—↑. I don't recommend disabling it because it is nice to have an indication of whether modalka-mode is active or not. Furthermore, one can make the current editing mode even more conspicuous by changing the cursor shape. I suggest using the vertical bar cursor in the insert mode and the box cursor in the normal mode. Modalka uses the cursor specified in the modalka-cursor-type variable, so the whole setup might look like this:

(setq-default cursor-type '(bar . 1))
(setq modalka-cursor-type 'box)

Customization

modalka-mode is a normal minor mode. This means that you can use the modalka-mode-hook to define mode-specific hooks. You can use the customization interface to customize Modalka-related variables like this: M-x customize-group modalka RET.

Other solutions

In this section I describe other solutions and compare them with this package. Some of the solutions are quite popular, others are almost not used. I attempt to guess why it is so and why Modalka may be worth trying out.

Evil

Emulation of the Vi-style modal editing for Emacs is provided by several different packages, but the most advanced is Evil. What's wrong with it? Emacs is very flexible and can be Vi, with some effort, but Emacs is not Vi. Emacs has different keybindings for movement, etc. that permeate its whole ecosystem. Once evil-mode is used to edit text, one needs to either accept that text editing is done with a set of key bindings that differs from everything else, or to try to convert Emacs further. To convert Emacs further one needs more bridge packages: evil-org, evil-smartparens, etc. The sort of conversion can never be fully complete. Evil by itself is fairly complex and hooks deep into Emacs internals. It can cause incompatibilities with other packages. It also makes it harder to hack Emacs.

Control Mode

Control Mode is essentially a hack. From my experience it has the following flaws:

If one works with overlays that have local key maps this mode cannot handle it. One needs to disable it to interact with the overlays (packages that implement text folding are an example of that).
If a minor mode is activated when control-mode is already enabled, it cannot catch this change and adapt. One needs to turn control-mode off and then reactivate it or to run a special command that re-generates the key bindings.
Generalizing the previous points, in Emacs, a given combination of keys may have different meanings depending on the situation. The automatic generation of key bindings that control-mode uses fixes keybindings every time and thus causes all sorts of problems.
Control mode generates more key bindings than necessary replacing key bindings that should not be used in the normal mode.

God Mode

God Mode can be considered an improvement on control-mode. However, compared to Modalka, God Mode has certain downsides:

Design decisions are made for you. You can change something (because it's Emacs), but forming the entire key map is not meant to be done by the user.
The implementation is far more hairy without additional benefits.
Unlike Modalka, God Mode doesn't work with input methods.
You don't need to write hooks to change the shape of cursor according to current mode with Modalka, it handles this for you.

Boon

Boon is a package for modal editing with emphasis on ergonomics. This package gives you complete implementation of a modal editing system similar to Vi. It may take some time to learn it and I'm not entirely sure it will make much difference. Modal editing is easier, but ergonomic layout in the normal mode is somewhat optional for most people. I value compatibility with the Emacs ecosystem more.

Fingers

Fingers is another attempt at ergonomic modal editing. The same thoughts that have been said regarding Boon can be repeated here. The differences between these packages are not very significant except for the fact that Fingers is optimized for the Workman keyboard layout.

Xah Fly Keys

Xah Fly Keys is a package for ergonomic modal editing optimized for Dvorak. It's rather big compared to Boon and Fingers. If you look at source code you'll see that it has a peculiar collection of editing primitives. For example one can capitalize text skipping words like “and”, “to”, “or”, etc.—functionality that is rarely found in this sort of a package. Good dose of Unicode support is guaranteed, too.

Ergoemacs Mode

According to the authors, Ergoemacs Mode supports modal editing and can even emulate god-mode. And that's not all:

You can either define your own modal keymap, or tell ergoemacs-mode that the keyboard layout is the same as the current layout, but with Alt (or control pressed, or swapped, or any sort of other key combination).

License

Distributed under GNU GPL, version 3.

mrkkrp / modalka