syntax_data: {"ast_node_type":"variable","tokens":[{"end":37,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let tupled_tys = match self {
context_before:     pub fn upvar_tys(self) -> &'tcx List<Ty<'tcx>> {
context_after:             UpvarArgs::Closure(args) => args.as_closure().tupled_upvars_ty(),