leanprover / leanprover/reference-manual
Better document when `cases` can be used
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doc-request
- Dominant language
- Lean
- Stars
- 129
- Forks
- 67
- Avg merge
- 1d 15h
- Merged PRs (30d)
- 16
Description
@kmill wrote a nice pithy summary on Zulip:
The rule is "cases will work if all the indices appearing in constructors are made of free variables and constructor applications (after unfolding everything)"
That should be in here.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by locating the reference-manual section that documents when cases can be used, then compare its current explanation with the Zulip summary quoted in the issue. Update the documentation to state the quoted rule clearly; done means the rule is present in the relevant section and the manual still builds or its documentation checks pass.
Written by the indexing model from the issue text.
Assessment
- Domain
- documentation
- Issue type
- Documentation
- Difficulty
- 2/5
- Estimated time
- 1-3 hours
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 48/100