split at hgo
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
w : Nat
aig : AIG α
distance : Nat
input : aig.RefStream w
curr : Nat
hcurr : curr ≤ w
s : aig.RefStream curr
res : AIG.RefStreamEntry α w
hgo :
  (if hidx : curr < w then
      if hdist : curr < distance then
        let res := aig.mkConstCached false;
        let aig_1 := res.aig;
        let zeroRef := res.ref;
        let_fun hfinal := ⋯;
        let s := s.cast hfinal;
        let input := input.cast hfinal;
        let s := s.pushRef zeroRef;
        go aig_1 input distance (curr + 1) ⋯ s
      else
        let s := s.pushRef (input.getRef (curr - distance) ⋯);
        go aig input distance (curr + 1) ⋯ s
    else
      let_fun hcurr := ⋯;
      { aig := aig, stream := hcurr ▸ s }) =
    res
⊢ ∀ (idx : Nat) (h1 : idx < aig.decls.size) (h2 : idx < res.aig.decls.size), res.aig.decls[idx] = aig.decls[idx]
case isTrue
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
w : Nat
aig : AIG α
distance : Nat
input : aig.RefStream w
curr : Nat
hcurr : curr ≤ w
s : aig.RefStream curr
res : AIG.RefStreamEntry α w
h✝ : curr < w
hgo :
  (if hdist : curr < distance then
      let res := aig.mkConstCached false;
      let aig_1 := res.aig;
      let zeroRef := res.ref;
      let_fun hfinal := ⋯;
      let s := s.cast hfinal;
      let input := input.cast hfinal;
      let s := s.pushRef zeroRef;
      go aig_1 input distance (curr + 1) ⋯ s
    else
      let s := s.pushRef (input.getRef (curr - distance) ⋯);
      go aig input distance (curr + 1) ⋯ s) =
    res
⊢ ∀ (idx : Nat) (h1 : idx < aig.decls.size) (h2 : idx < res.aig.decls.size), res.aig.decls[idx] = aig.decls[idx]

case isFalse
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
w : Nat
aig : AIG α
distance : Nat
input : aig.RefStream w
curr : Nat
hcurr : curr ≤ w
s : aig.RefStream curr
res : AIG.RefStreamEntry α w
h✝ : ¬curr < w
hgo :
  (let_fun hcurr := ⋯;
    { aig := aig, stream := hcurr ▸ s }) =
    res
⊢ ∀ (idx : Nat) (h1 : idx < aig.decls.size) (h2 : idx < res.aig.decls.size), res.aig.decls[idx] = aig.decls[idx]