Reactivity Model

[A1Liu]

• [x] Make Runner threadsafe
• [ ] Save outputs for future use
• [x] Set up sheet command system so that we can send events to the sheet
• [ ] I guess just stream data from output buffer in Rust code into the terminal
• [ ] Store command ID on the cell?
• [ ] Maybe have a GC system for commands or something, idk
• [ ] Need proper two-way communication so that when a cell resets its state the rust side can create a new graph for it

Tauri events: https://tauri.app/v1/guides/features/events/

[A1Liu]

Options

Implement GC and tracking manually

use IDs to track reference lifetimes, and do our own garbage collection

Implement GC implicitly using Arc

~Runs keep Arc to their inputs, stream results as needed~

Final decision

• Cells hold references to their currently active runner

• Poll cell using cell ID instead of run ID

• Add cursors + buffering to runners

• Graph is separate data structure between cells, not runners

• Graph created during startup using start method of the run command

• pollCell(CellId) -> { uuid of runner, results, etc. } - frontend should poll cells instead of commands/runners

• RunCtx.read_from_cell() - Reads the current runnable from the cell and adds the dependency relation to the RunGraph

• Runner { generation: u32, } // generation counter prevents cycles -

• Re-runs are serialized, waiting until all dependencies are re-started before modifying the graph with the next set of modifications

• If a command is still running while a graph edit is happening, it must be restarted (can consider doing something more complicated in the future, but whatever for now)

Need to use RunGraph instead of CellGraph so that there's no race conditions which produce implicit cycles Also probably need a version ID on the generation counter

[A1Liu]

Maybe instead of having super complicated threading model, use ideas from tick system in S.js to serialize dependency graph production

[A1Liu]

petgraph::GraphMap - https://github.com/petgraph/petgraph

[A1Liu]

Use start() -> RunResult to synchronously create graph w/ initial dependencies mapped out

[A1Liu]

Plan:

1. Set up buffering using files instead of in-memory stuff (notify crate or tail -f -c +1 FILE)
2. Run polling for cells instead of runners
3. Stdin
4. Dependency Graph