Theorem: SSAScope.get_to_getT
Proof state before:
α σ : Type
ε : σ → Type
δ : Dialect α σ ε
name : SSAVal
τ : MLIRType δ
head : SSAVal × (τ : MLIRType δ) × MLIRType.eval τ
tail : List (SSAVal × (τ : MLIRType δ) × MLIRType.eval τ)
HInd :
  get name tail τ =
    match getT name tail with
    | none => none
    | some { fst := τ', snd := v' } =>
      if H : τ' = τ then
        some
          (cast
            (_ :
              (match τ' with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit) =
                match τ with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit)
            v')
      else none
⊢ (if H : head.fst = name then
      if H' : head.2.fst = τ then
        some
          (cast
            (_ :
              (match head.2.fst with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit) =
                match τ with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit)
            head.2.snd)
      else none
    else get name tail τ) =
    match if head.fst = name then some { fst := head.2.fst, snd := head.2.snd } else getT name tail with
    | none => none
    | some { fst := τ', snd := v' } =>
      if H : τ' = τ then
        some
          (cast
            (_ :
              (match τ' with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit) =
                match τ with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit)
            v')
      else none
Tactic:
byCases Hname: head.fst = name
Proof state after:
case h2
α σ : Type
ε : σ → Type
δ : Dialect α σ ε
name : SSAVal
τ : MLIRType δ
head : SSAVal × (τ : MLIRType δ) × MLIRType.eval τ
tail : List (SSAVal × (τ : MLIRType δ) × MLIRType.eval τ)
HInd :
  get name tail τ =
    match getT name tail with
    | none => none
    | some { fst := τ', snd := v' } =>
      if H : τ' = τ then
        some
          (cast
            (_ :
              (match τ' with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit) =
                match τ with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit)
            v')
      else none
Hname : ¬head.fst = name
⊢ get name tail τ =
    match getT name tail with
    | none => none
    | some { fst := τ', snd := v' } =>
      if h : τ' = τ then
        some
          (cast
            (_ :
              (match τ' with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit) =
                match τ with
                | MLIRType.float a => Float
                | MLIRType.int signedness sz => FinInt sz
                | MLIRType.tensor1d => Tensor1D
                | MLIRType.tensor2d => Tensor2D
                | MLIRType.tensor4d => Tensor4D
                | MLIRType.index => ℤ
                | MLIRType.undefined a => Unit
                | MLIRType.extended σ => ε σ
                | MLIRType.erased => Unit)
            v')
      else none