Better error message for indentation problems?
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P-medium
- Dominant language
- Lean
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Description
Consider:
example : ∀ (p : Prop), p → p := by
intros p h
exact h
The error message on the third line is unexpected identifier; expected command. Is it technically conceivable that it could be something like unexpected unindent instead?
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Open a pull request that references the issue number.
Research direction
Reproduce the issue with the Lean snippet shown and compare the diagnostic produced at the misindented exact h line. Trace the parser or indentation-error handling from that failure; done means the diagnostic clearly identifies the unexpected unindent, with tests covering the example.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Feature
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100