unfold go
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
w : Nat
aig : AIG α
curr : Nat
hcurr : curr ≤ w
discr : aig.Ref
lhs rhs : aig.RefStream w
s : aig.RefStream curr
⊢ aig.decls.size ≤ (go aig curr hcurr discr lhs rhs s).aig.decls.size
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
w : Nat
aig : AIG α
curr : Nat
hcurr : curr ≤ w
discr : aig.Ref
lhs rhs : aig.RefStream w
s : aig.RefStream curr
⊢ aig.decls.size ≤
    (if hcurr : curr < w then
            let input := { discr := discr, lhs := lhs.getRef curr hcurr, rhs := rhs.getRef curr hcurr };
            let res := aig.mkIfCached input;
            let aig_1 := res.aig;
            let ref := res.ref;
            let_fun this := ⋯;
            let discr_1 := discr.cast this;
            let lhs_1 := lhs.cast this;
            let rhs_1 := rhs.cast this;
            let s := s.cast this;
            let s := s.pushRef ref;
            go aig_1 (curr + 1) ⋯ discr_1 lhs_1 rhs_1 s
          else
            let_fun this := ⋯;
            { aig := aig, stream := this ▸ s }).aig.decls.size