commutable

com·mut·a·ble

/kəˈmyo͞otəbəl/

1. (of a place or journey) allowing regular commuting to and from work.
2. capable of being exchanged or converted.

commutable is a library for Jupyter Notebook operations, helping to enable history stored as a series of immutable notebooks.

Principles

• A notebook document is immutable. It is never mutated in-place.
• Changes to a notebook document are encapsulated into operations that take a previous version and return a new one.
• History is represented as a list of states, with past on one end, the present on the other, and an index that can back up into 'undo states'.
• Modifying a notebook document causes any future states to be thrown away.

Credits to Tom MacWright for the outline.

Inspired by

• Elm's time traveling debugger
• Practical Undo
• Live React: Hot Reloading with Time Travel

Roadmap

Provide utilities for working with IPython/Jupyter notebooks under their common operations.

• Convert from on disk v4 format to in-memory format
• Convert from v3 to v4
• Design cell operations
• Convert from in-memory to disk format