Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
5306a3469d
This PR fixes a bug in the propagation rules for `ite` and `dite` used
in `grind`. The bug prevented equalities from being propagated to the
satellite solvers. Here is an example affected by this issue.
```lean
example
[LE α] [LT α] [Std.IsLinearOrder α] [Std.LawfulOrderLT α]
[Lean.Grind.CommRing α] [DecidableLE α] [Lean.Grind.OrderedRing α]
(a b c : α) :
(if a - b ≤ -(a - b) then -(a - b) else a - b) ≤
((if a - c ≤ -(a - c) then -(a - c) else a - c) + if c - d ≤ -(c - d) then -(c - d) else c - d) +
if b - d ≤ -(b - d) then -(b - d) else b - d := by
grind
```
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| RELEASES.md | ||
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