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feat(init/wf): simplify definition acc.drec

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Floris van Doorn 2016-02-08 20:15:57 -05:00 committed by Leonardo de Moura
parent e14d4a4c0c
commit 42b78962f9
1 changed files with 1 additions and 6 deletions
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7
hott/init/wf.hlean
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@ -33,12 +33,7 @@ namespace acc
(h₁ : Π (x : A) (acx : Π (y : A), R y x → acc R y),
(Π (y : A) (ryx : R y x), C y (acx y ryx)) → C x (acc.intro x acx))
{a : A} (h₂ : acc R a) : C a h₂ :=
begin
refine acc.rec _ h₂ h₂,
intro x acx ih h₂,
exact transport (C x) !acc_eq (h₁ x acx (λ y ryx, ih y ryx (acx y ryx)))
end
acc.rec h₁ h₂
end acc
inductive well_founded [class] {A : Type} (R : A → A → Type) : Type :=