{"ast_node_type":"variable","tokens":[{"end":77,"kind":"keyword","start":0,"text":"let"}]}
        let typeck_root_def_id = self.typeck_root_def_id(def_id.to_def_id());
        // as they are part of the same "inference environment".
        if typeck_root_def_id != def_id.to_def_id() {