{"ast_node_type":"variable","tokens":[{"end":65,"kind":"keyword","start":0,"text":"if"}]}
                    if let Some(trait_ref) = dyn_ty.principal() {
                    // Manually visit to actually see the trait's `DefId`. Type visitors won't see it
                        let ExistentialTraitRef { def_id, args, .. } = trait_ref.skip_binder();