Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
This PR implements extended `induction`-inspired syntax for `mvcgen`,
allowing optional `using invariants` and `with` sections.
```lean
mvcgen
using invariants
| 1 => Invariant.withEarlyReturn
(onReturn := fun ret seen => ⌜ret = false ∧ ¬l.Nodup⌝)
(onContinue := fun traversalState seen =>
⌜(∀ x, x ∈ seen ↔ x ∈ traversalState.prefix) ∧ traversalState.prefix.Nodup⌝)
with mleave -- mleave is a no-op here, but we are just testing the grammar
| vc1 => grind
| vc2 => grind
| vc3 => grind
| vc4 => grind
| vc5 => grind
```
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| RELEASES.md | ||
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