byCases H: head.fst = v <;> try apply cast_eq
case cons
α σ : Type
ε : σ → Type
α✝ σ✝ : Type
ε✝ : σ✝ → Type
δ : Dialect α✝ σ✝ ε✝
v : SSAVal
τ : MLIRType δ
val : MLIRType.eval τ
head : SSAVal × (τ : MLIRType δ) × MLIRType.eval τ
nil : List (SSAVal × (τ : MLIRType δ) × MLIRType.eval τ)
tail_ih✝ : get v (set v τ val nil) τ = some val
⊢ get v (if head.fst = v then (head.fst, { fst := τ, snd := val }) :: nil else head :: set v τ val nil) τ = some val
case cons.h2
α σ : Type
ε : σ → Type
α✝ σ✝ : Type
ε✝ : σ✝ → Type
δ : Dialect α✝ σ✝ ε✝
v : SSAVal
τ : MLIRType δ
val : MLIRType.eval τ
head : SSAVal × (τ : MLIRType δ) × MLIRType.eval τ
nil : List (SSAVal × (τ : MLIRType δ) × MLIRType.eval τ)
tail_ih✝ : get v (set v τ val nil) τ = some val
H : ¬head.fst = v
⊢ get v (set v τ val nil) τ = some val