let p₂ := step hyp.right
case cons
R : Type u_2
inst✝² : Ring R
inst✝¹ : DecidableEq R
X : Type u_1
inst✝ : DecidableEq X
f g : X → R
h : X
t : List X
step : beqOnSupport t f g = true → equalOnList t f g
hyp : f h = g h ∧ List.foldr (fun a r => decide (f a = g a) && r) true t = true
⊢ f h = g h ∧ equalOnList t f g
case cons
R : Type u_2
inst✝² : Ring R
inst✝¹ : DecidableEq R
X : Type u_1
inst✝ : DecidableEq X
f g : X → R
h : X
t : List X
step : beqOnSupport t f g = true → equalOnList t f g
hyp : f h = g h ∧ List.foldr (fun a r => decide (f a = g a) && r) true t = true
p₂ : equalOnList t f g := step hyp.right
⊢ f h = g h ∧ equalOnList t f g