closes 7690, adds: @app.cell(expanded_output=True)

[csp256]

📝 Summary

Closes #7690

This introduces the ability to annotate a cell with @app.cell(expand_output=True) to cause that cell's output to be automatically expanded by default when the user loads the notebook.

This PR does not provide a way to cause this behavior from the web UI.

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[csp256]

I have read the CLA Document and I hereby sign the CLA

[csp256]

recheck

[akshayka]

Hey @csp256, in #7690 we decided against per-cell configuration. We were converging toward pyproject.toml / user configuration:

# /// script
# [tool.marimo.display]
# expand_outputs = True
# ///

I think this needs a bit more discussion in the issue before proceeding for PR. There were unresolved questions of how a global expand outputs configuration would interact with possible configuration for text outputs. It would be good to study what other projects do as well, and form an opinion of what works and what doesn't

[csp256]

I guess I will continue the discussion on the issue. While I agree broad defaults are a good idea, I think that the per-cell configurable behavior has some benefits.

[csp256]

@akshayka Also, you should probably update CONTRIBUTING.md with the restriction that all public API changes need to be approved before PR. It currently just says:

Please reach out to the marimo team before starting work on a large contribution.

I would not have considered this a large contribution.

[manzt]

Thanks, we have updated the contributing guide to expand upon contributions #9153.