leanprover-community / leanprover-community/lean
nested congr doesn't work in converter mode
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bug
- Dominant language
- C++
- Stars
- 434
- Forks
- 79
- PR merge metrics
- No merged PRs in 30d
Description
Description
In the code snippet below, the second congr raises an error, presumably because I'm already "inside" an funext. In my actual case I wanted to rewrite inside a double integral.
example : (∃ x y : ℕ, x = y) = true :=
begin
conv { to_lhs, congr, funext, congr, }
end
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 reproducing the example through the conv and congr converter entry points, then inspect how nested funext state is handled. Done means the second congr works in converter mode for the shown example and supports the intended nested rewrite inside a double integral.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100