hedit

hedit is a lightweight, terminal-based text editor written in hica. It pairs modern editor UX (standard keybindings, mouse support, split panes, syntax highlighting) with hica's algebraic effects and Perceus-based memory management (FBIP).

Features

• Familiar keybindings — Ctrl-s/Ctrl-o/Ctrl-q for save/open/quit, readline-style motions (Ctrl-a/e, Meta-f/b, Ctrl-k, Ctrl-w, …), undo/redo, a shared clipboard
• Selections — set a mark with Ctrl-Space, extend it with the arrow keys, then copy/cut/paste just the selected text
• Incremental search — Ctrl-f to search live as you type, Ctrl-Right/Ctrl-Left to jump between wrapping matches
• Multiple buffers — a buffer ring (Meta-o/n/p/w) with a tabline showing every open file
• Split panes — vertical and horizontal splits (Meta-v/Meta-h), focus movement between panes, mouse-driven divider resizing
• Mouse support — click to place the cursor, drag to select, click/drag to move focus or resize a split, scroll to move the viewport
• Syntax highlighting — a fast, built-in line-by-line lexer highlights hica/koka source
• Live keybindings overlay — Ctrl-g shows every currently bound chord, generated straight from the active bindings
• Scriptable — settings, keybindings, and plugins are all just HiLisp (see below)

Full reference with every chord: docs/hedit-cheatsheet.md (or press Ctrl-g inside hedit for a live overlay).

Quick Install

Using standard curl:

curl -fsSL https://github.com/cladam/hedit/releases/latest/download/install.sh | sh

Or install hedit using hicurl:

hicurl https://github.com/cladam/hedit/releases/latest/download/install.sh | sh

Installs binary (macos-arm64, linux-arm64, linux-x86_64) to ~/.local/bin. Override target location with HEDIT_INSTALL_DIR=/usr/local/bin.

HEDIT_INSTALL_DIR=/usr/local/bin curl -fsSL https://github.com/cladam/hedit/releases/latest/download/install.sh | sh
# Or with hicurl
HEDIT_INSTALL_DIR=/usr/local/bin hicurl https://github.com/cladam/hedit/releases/latest/download/install.sh | sh

Note: No Windows support!

Usage

hica build -o hedit           # compile to ./hedit
./hedit                       # open an empty scratch buffer
./hedit somefile.txt          # open a real file

Default keybindings (overridable from init.hl):

• File: Ctrl-s save, Ctrl-o open-file prompt, Ctrl-q quit (with 2+ panes open, closes the active pane/buffer first)
• Readline-style editing: Ctrl-a/Ctrl-e line start/end, Ctrl-d delete-forward, Ctrl-k kill-line, Ctrl-w kill-word-back, Meta-f/Meta-b word forward/back, Meta-d kill-word-forward, Meta-l kill-whole-line
• Clipboard & history: Ctrl-c/Ctrl-v copy/paste, Ctrl-y yank (same clipboard slot as paste), Ctrl-z undo, Ctrl-r redo
• Selection: Ctrl-Space set/clear the mark, use arrows or navigation chords to select, Meta-a select all; with a selection active, Ctrl-c/Ctrl-v copy/replace just the selected text instead of the whole line
• Search: Ctrl-f open search prompt, Ctrl-Right next occurance, Ctrl-Left previous occurance.
• Buffers: Meta-o/Meta-n/Meta-p/Meta-w new/next/prev/close buffer
• Split panes: Meta-v/Meta-h open a vertical/horizontal split prompt (type a path + Enter to open that file in the new pane, or a bare Enter to duplicate the current buffer), Meta-Arrows move focus to the nearest pane, Meta-Tab cycles through panes
• Help: Ctrl-g toggle the keybindings overlay

Command-line flags

hedit                                   # empty scratch buffer
hedit file.txt                          # open a file
hedit +42 file.txt                      # open at line 42
hedit +42:8 file.txt                    # open at line 42, column 8
hedit --readonly file.txt               # -R — open read-only (Save disabled)
hedit --tabsize 2 file.txt              # override tabsize for this run
hedit --config init.hl file.txt         # load config from elsewhere
hedit --no-config file.txt              # skip init.hl entirely
hedit --help / --version

CLI flags always win over init.hl, e.g. --tabsize overrides a (set "tabsize" ...) in the loaded config.

Cloning

Because HiLisp is a submodule:

git clone --recurse-submodules https://github.com/cladam/hedit.git
# or, if already cloned:
git submodule update --init --recursive

To bump the pinned HiLisp version:

git submodule update --remote lib/hilisp

Configuration & plugins: HiLisp

hedit uses HiLisp (a small Lisp interpreter written in hica) as its configuration and plugin language. Settings, keybindings, and plugins are all written as .hl files evaluated by the embedded HiLisp interpreter.

HiLisp lives as a git submodule under lib/hilisp/ and is compiled together with hedit (see hica.hml).

Example init.hl

;; ~/.config/hedit/init.hl

(set "tabsize"     4)
(set "auto-indent" true)
(set "theme"       "ilseon")

(bind "Ctrl-s" 'save)
(bind "Ctrl-q" 'quit)
(bind "Meta-w" 'close-buffer)

Config discovery order (first hit wins):

1. $XDG_CONFIG_HOME/hedit/init.hl (or $HOME/.config/hedit/init.hl)
2. $HOME/.hedit.hl

If neither exists, hedit runs with hard-coded defaults.

See examples/init.hl for all available options

API surface

Built-in	Purpose
(set key value)	Set a configuration value
(get key)	Read a configuration value
(bind keystroke action)	Map a keystroke to a named built-in action
(plugin "name")	Opt into loading plugins/<name>/plugin.hl (see Plugins below)
(on 'event (fn (...) ...))	Register a hook for a lifecycle event (see Plugins below)

Plugins

A plugin is a regular .hl file, hedit doesn't auto-discovers plugins, you opt in by name from init.hl, and hedit resolves that name to a file next to init.hl itself.

1. Write the plugin file at plugins/<name>/plugin.hl, in the same directory as the init.hl that will load it (i.e. next to whichever one of $XDG_CONFIG_HOME/hedit/init.hl, $HOME/.config/hedit/init.hl, or $HOME/.hedit.hl you're using):

;; ~/.config/hedit/plugins/greeter/plugin.hl
(on 'buffer-open (fn (path) "Welcome to hedit!"))

2. Wire it up with (plugin "name") in init.hl:

;; ~/.config/hedit/init.hl
(plugin "greeter")

Available hooks, registered with (on 'event (fn (...) ...)) (more than one plugin/hook can register for the same event; they run in registration order):

Event	Args	Fires
'buffer-open	(path)	A buffer finished loading ("" for a scratch buffer); on startup and on new-buffer/open
'pre-save	(path)	Before writing a named buffer to disk
'post-save	(path)	After a successful save
'pre-action	(action-name)	Before every resolved action (the same name (bind ...) targets)
'quit	()	Once, best-effort, right before hedit exits

Two conventions apply across all hooks instead of new builtins:

• Cancel: if any pre-save/pre-action hook returns false, the save/action is skipped. Quit is the one exception — it always proceeds no matter what a pre-action hook returns, so a plugin can never trap the editor open.
• Status: if a hook returns a string, it becomes the next status-bar message.

A broken or missing plugin.hl surfaces a one-line status message naming the plugin and never blocks init.hl or any other plugin from loading.

See examples/plugins/ for six reference plugins and examples/init.hl for the (plugin ...) opt-in syntax.

License

MIT – see LICENSE.