65e55ac094
This PR fixes a bug in the projection over constructor propagator used in `grind`. It may construct type incorrect terms when a equivalence class contains heterogeneous equalities. closes #9769
35 lines
851 B
Text
35 lines
851 B
Text
def Foo (n : Nat) := Σ (m : Nat), {f : Fin (n + 2) → Fin (m + 2) // f 0 = 0}
|
|
|
|
variable (n : Nat)
|
|
|
|
def Foo.e (f : Foo n) := f.2.1
|
|
|
|
def Foo.id : (Foo n) := ⟨n, ⟨fun x => x, rfl⟩⟩
|
|
|
|
def Foo.EqId (f : Foo n) : Prop :=
|
|
f = (Foo.id _)
|
|
|
|
structure Bar {n m : Nat} (f : Fin (n + 2) → Fin (m + 1)) : Prop where
|
|
out : f 1 = 1
|
|
|
|
/--
|
|
error: `grind` failed
|
|
case grind
|
|
n : Nat
|
|
f : Foo n
|
|
this : Bar fun x => x
|
|
h : ¬(Foo.EqId n f → Bar (Foo.e n f))
|
|
⊢ False
|
|
-/
|
|
#guard_msgs in
|
|
theorem EqIdToZero (f : Foo n) : f.EqId → Bar f.e := by
|
|
have : Bar (fun x => x : Fin (n + 2) → Fin (n + 2)) := ⟨rfl⟩
|
|
grind -verbose [Foo.e, Foo.id, Foo.EqId]
|
|
|
|
-- A simpler example that is provable and also triggers issue #9769
|
|
|
|
structure Boo (n : Nat) where
|
|
x : Nat
|
|
|
|
example (a : Boo 1) (n : Nat) : a ≍ Boo.mk (n := n) b → n = 1 → a.x = b := by
|
|
grind
|