Runestone uses GitHub's Tree-sitter to parse code to a syntax tree which is used for features that require an understanding of the code in the editor, for example syntax highlighting.
- Syntax highlighting using Tree-sitter's captures.
- Line numbers.
- Show invisible characters (tabs, spaces and line breaks).
- Insertion of character pairs, e.g. inserting the trailing quotation mark when inserting the leading.
- Customization of colors and fonts using the Theme protocol.
- Toggle line wrapping on and off.
- Adjust line heights.
- Add a page guide.
- Automatically detects if a file is using spaces or tabs for indentation.
Please refer to the Getting Started article in the documentation.
The documentation os all public types is available at docs.runestone.app. The documentation is generated from the Swift code using Apple's DocC documentation compiler.
Runestone was built to be fast. It's good performance is by far mostly thanks to Tree-sitter's incremental parsing and AvalonEdit's approach for managing lines in a document.
When judging the performance of Runestone, it is key to build your app in the release configuration. The optimizations applied by the compiler when using the release configuration becomes very apparent when opening large documents.
- Tree-sitter is used to parse code incrementally.
- Line management is translated to Swift from AvalonEdit.
- swift-tree-sitter which Runestone's Swift bindings for Tree-sitter is heavily inspired by.
- Detection of indent strategy inspired by auto-detect-indentation.
- And last (but not least!), thanks a ton to Alexander Blach (developer of Textastic), Till Konitzer (developer of Essayist), Greg Pierce (developer of Drafts) and Max Brunsfeld (developer of Tree-sitter) for pointing me in the right direction when I got stuck.