cases σ
Γ : Type
inst✝ : Alphabet Γ
σ : (RankedAlphabet.lift Γ).alphabet
w : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) σ) → Term (RankedAlphabet.lift Γ) Empty
hi : ∀ (a : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) σ)), ∃ a_1, treeₑ a_1 = w a
⊢ ∃ a, treeₑ a = app σ w
case none
Γ : Type
inst✝ : Alphabet Γ
w : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) none) → Term (RankedAlphabet.lift Γ) Empty
hi : ∀ (a : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) none)), ∃ a_1, treeₑ a_1 = w a
⊢ ∃ a, treeₑ a = app none w

case some
Γ : Type
inst✝ : Alphabet Γ
val✝ : Γ
w : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) (some val✝)) → Term (RankedAlphabet.lift Γ) Empty
hi : ∀ (a : Fin (RankedAlphabet.rank (RankedAlphabet.lift Γ) (some val✝))), ∃ a_1, treeₑ a_1 = w a
⊢ ∃ a, treeₑ a = app (some val✝) w