exact ⟨_, obj?_some_nested h hi.choose_spec⟩
α : Type
inst✝ : Hierarchical α
rtr₁ : α
cpt : Component.Valued
i : ID
v : Value
rtr₂ : α
j✝ : ID
rtr₁✝ rtr₂✝ : α
n₁✝ n₂✝ : Component.type α Component.rtr
a✝² : rtr₁✝ ≃[Component.rtr][j✝] rtr₂✝
h : rtr₁✝{Component.rtr}{j✝} = some n₁✝
a✝¹ : rtr₂✝{Component.rtr}{j✝} = some n₂✝
a✝ : LawfulMemUpdate cpt i v n₁✝ n₂✝
hi : ∃ o, n₁✝[Component.val cpt][i] = some o
⊢ ∃ o, rtr₁✝[Component.val cpt][i] = some o
no goals