assumption
case none
α qs : Type
M : DFA α qs
w : Word { x // x ∈ M.Z }
q : { x // x ∈ M.Q }
x : { x // x ∈ M.Z }
xs : List { x // x ∈ M.Z }
hq' : M.δ (q, x) = none
a✝¹ : { x // x ∈ M.Q }
H✝ : a✝¹ ∈ M.δ (q, x)
a✝ :
  (do
      let r' ← constrRun xs a✝¹
      some (NFA.Run.step q ⋯ r' ⋯)) =
    none
⊢ M.δ (q, x) = none
no goals