unfold go
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
curr a✝ : Nat
hcurr : curr ≤ a✝
aig : AIG α
cin : aig.Ref
lhs rhs : aig.RefStream a✝
⊢ aig.decls.size ≤ (go aig curr hcurr cin lhs rhs).aig.decls.size
α : Type
inst✝² : BEq α
inst✝¹ : Hashable α
inst✝ : DecidableEq α
curr a✝ : Nat
hcurr : curr ≤ a✝
aig : AIG α
cin : aig.Ref
lhs rhs : aig.RefStream a✝
⊢ aig.decls.size ≤
    (if hidx : curr < a✝ then
            let lin := lhs.getRef curr hidx;
            let rin := rhs.getRef curr hidx;
            let res := mkFullAdderCarry aig { lhs := lin, rhs := rin, cin := cin };
            let_fun this := ⋯;
            let aig_1 := res.aig;
            let carryRef := res.ref;
            let lhs_1 := lhs.cast this;
            let rhs_1 := rhs.cast this;
            go aig_1 (curr + 1) ⋯ carryRef lhs_1 rhs_1
          else { aig := aig, ref := cin }).aig.decls.size