{"ast_node_type":"variable","tokens":[{"end":72,"kind":"keyword","start":0,"text":"let"}]}
                let hir_node = tcx.hir_node_by_def_id(self.body_def_id);
                // only use the span of the predicate clause (#90869)
                if let Some(hir::Generics { predicates, .. }) = hir_node.generics() {