lean2/tests/lean/run/local_eqns2.lean

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import data.fin
open fin nat
definition nz_cases_on {C : Π n, fin (succ n) → Type}
(H₁ : Π n, C n (fz n))
(H₂ : Π n (f : fin n), C n (fs f))
{n : nat}
(f : fin (succ n)) : C n f :=
begin
reverts (n, f),
show ∀ (n : nat) (f : fin (succ n)), C n f
| m (fz m) := by apply H₁
| m (fs f') := by apply H₂
end