`revert` does not respect the argument order
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Description
Prerequisites
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Description
The revert tactic ignores the order of its arguments
Context
[Broader context that the issue occured in. If there was any prior discussion on the Lean Zulip, link it here as well.]
Steps to Reproduce
example (a b c : Nat) : a * b * c = 1 := by
revert c a b
sorry
Expected behavior: Goal is ∀ (c a b : Nat), a * b * c = 1 like it was in Lean 3
Actual behavior: Goal is ∀ (a b c : Nat), a * b * c = 1, ignoring the argument order
Versions
4.4.0-rc1
Impact
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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 with the minimal revert c a b example in the issue and compare the produced goal with the expected order. Locate the Lean 4 revert tactic implementation, then add a regression test showing that argument order is preserved and run the relevant tactic tests.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Clearly specified
- Newbie friendliness
- 45/100