elm-text-editor

A flexible text editor written in Elm

Check out the demo

Note:

• This project is not published yet on package.elm-lang.org
• I would not consider this project ready for use in production, since it's missing major features like undo history, scrolling, and line wrap

Features / Architecture

This library implements an editor (duh) and a buffer. The buffer is separate from the editor to allow multiple editors to use the same buffer, such as in a multi-panel text editor.

Note: There's a checkmark next to implemented features

Buffer

• file content
• undo history
• save status
• syntax highlighting (cached)
• decorations (eg underlines, tooltips, gutter icons)

The buffer implementation has helper functions for manipulating its content, like finding the end of a word.

Editor

• cursor location
• selection
• rendering to the DOM
• UI interaction (mouse and keyboard)
• scroll position
• auto-complete dialog
• open decorations (in other words, decorations exist in the buffer but each editor tracks open decorations)
• line wrap

This project is missing many of the features of Ace and CodeMirror, but Ace and CodeMirror have had quite a head start about 7 years.

Previous work and Inspiration

The editor behavior and keyboard shortcuts are based on Atom (because that's the editor I'm most familiar with).

Ace and CodeMirror are text editors designed to work in a web browser. They're both written in JavaScript, so integration with Elm is pretty meh.

Janiczek recently demonstrated a text editor in pure elm, which implements work-arounds for several issues I had faced in the past when creating a pure elm editor.

I hope this inspires somebody to try do some stuff in Elm they’ve been needing but seemed too big / hard for them! You might, like me with this project, find out it’s in your reach - no doubt thanks to Elm
- Janiczek