apply ys.recOnList (motive:=λ ys=>∀ xs hxsys haxs, (insertWithAux f xs ys hxsys a b haxs).val.fst.boundLeft c)
α : Type u
r : α → α → Prop
inst✝¹ : StrictLinearOrder r
inst✝ : DecidableRel r
β : α → Type v
f : (a : α) → β a → β a → Option (β a)
ys : KVChain r β
a : α
b : β a
c : α
hac : r a c
⊢ ∀ {xs : KVChain (flip r) β} {hxsys : hingeable xs ys} {haxs : boundLeft a xs},
    boundLeft c (insertWithAux f xs ys hxsys a b haxs).val.fst
case nil
α : Type u
r : α → α → Prop
inst✝¹ : StrictLinearOrder r
inst✝ : DecidableRel r
β : α → Type v
f : (a : α) → β a → β a → Option (β a)
ys : KVChain r β
a : α
b : β a
c : α
hac : r a c
⊢ ∀ (xs : KVChain (flip r) fun a => β a) (hxsys : hingeable xs KVChain.nil) (haxs : boundLeft a xs),
    boundLeft c (insertWithAux f xs KVChain.nil hxsys a b haxs).val.fst

case cons
α : Type u
r : α → α → Prop
inst✝¹ : StrictLinearOrder r
inst✝ : DecidableRel r
β : α → Type v
f : (a : α) → β a → β a → Option (β a)
ys : KVChain r β
a : α
b : β a
c : α
hac : r a c
⊢ ∀ (a_1 : α) (b_1 : β a_1) (xs : KVChain r fun a => β a) (haxs : boundLeft a_1 xs),
    (fun ys =>
          ∀ (xs : KVChain (flip r) fun a => β a) (hxsys : hingeable xs ys) (haxs : boundLeft a xs),
            boundLeft c (insertWithAux f xs ys hxsys a b haxs).val.fst)
        xs →
      (fun ys =>
          ∀ (xs : KVChain (flip r) fun a => β a) (hxsys : hingeable xs ys) (haxs : boundLeft a xs),
            boundLeft c (insertWithAux f xs ys hxsys a b haxs).val.fst)
        (KVChain.cons a_1 b_1 xs haxs)