Use cases to account for:

- Typing math expressions
- Invalid and incomplete expressions
  - Empty slots (like an exponent with nothing typed in it yet)
  - Unpaired brakets
- Live editing/multiplayer (CRDT or OT)
- Editable/static
  - Fully editable input
  - Fully static input
  - Editable slot embedded within static
  - Deeper nesting–editable within static within editable...
- Syntax highlighting
- Plugins (allow new types of things to be defined within the AST as a plugin; for example, a new operator or the concept of matrices)
- Programmatic edits being performed without losing cursor position & focus state
- Embedding non-math elements within math (such as a plain text input, an image, a footnote marker, an emoji, etc)
- Use within multiple component systems (React/Svelte/Vue/etc) or without one

Design decisions:

- Use plugins to define...
  a. Types of nodes in the AST
  b. How to respond to keyboard events (or maybe how to handle operations; can plugins define new types of operations?)
  c. Rules about what nodes are allowed to contain
  d. How to render/display output (perhaps in a constrained way to maintain consistency–maybe the plugin generates some representation of what to display, but does not directly touch the DOM)
  e. Post-processing that happens between completion of AST and render time (eg. syntax highlighting, custom syntax highlighting for a specific use case or based on external knowledge)
  f. Styling (allow styles to be fully customized by a plugin, including performing logic and then styling based on that–see syntax highlighting)
  g. Styling & appearance of cursors/selections
- Define in the core...
  - Accepting keyboard events using a hidden input
  - What a "location" is and how that enables cursors/ranges
- Explicitly encode editing events as operations
  - Keyboard event --> operation --> updated state & focus/cursor
  - Handle multiplayer/syncing of operations
- Minimal dependencies; no reliance on a component library (but provide thin wrapper libraries in many component systems)