{"ast_node_type":"other","tokens":[{"end":81,"kind":"keyword","start":0,"text":"(ty::UpvarCapture::ByRef(ref_a),"}]}
            (ty::UpvarCapture::ByRef(ref_a), ty::UpvarCapture::ByRef(ref_b)) => {
            }
                match (ref_a, ref_b) {