Isar-style proof framework for Lean

Develop and assess an Isabelle/Isar-style framework for Lean that supports the structuring of readable formal proofs and assists students in organizing their proofs.

Background

The paper discusses the have-tactic pattern as a useful way to state intermediate goals in Lean, while noting that it is not always the best presentation style for polished proofs. It contrasts Lean’s support for this pattern with the Isabelle/Isar framework, where structured proof presentation is more directly supported.

The authors explicitly hypothesize that a comparable framework could be developed for Lean and that it might improve students’ proof organization. The development and educational effectiveness of such a framework remain unresolved.

References

We hypothesize that a similar framework could be developed for Lean and this might help students to structure their proofs in a more readable way.

— Tutte's theorem as an educational formalization project  (2504.18146 - Otte, 25 Apr 2025) in Section 3.2.1, subsection “Example: have-tactic pattern” (\cref{subsec:have-tac})