{"ast_node_type":"function","tokens":[{"end":98,"kind":"keyword","start":0,"text":"fn"}]}
            fn is_sub_scope(&self, sub_id: hir::ItemLocalId, super_id: hir::ItemLocalId) -> bool {
            // Check scope of binding.
                let scope_tree = self.fcx.tcx.region_scope_tree(self.fcx.body_id);