This article delves into the intricate engineering details of Paper as a TextView-based text editor for Apple platforms. It explores the components such as NSTextView, NSTextStorage, NSLayoutManager, and UITextView that make up the editing experience. The article highlights the complexity and layers of TextView, as well as the efficiency in updating styling attributes. Surprisingly, the editor includes a Preview Mode for rich text editing and a unique algorithm to optimize typing speed by selectively re-parsing Markdown structure. Additionally, meta attributes play a vital role in features like formatting shortcuts, chapter navigation, and content conversion.
https://papereditor.app/internals