syntax_data: {"ast_node_type":"other","tokens":[{"end":68,"kind":"keyword","start":0,"text":"ty::Tuple(..)"}]}
source_snippet:             ty::Tuple(..) => self.tupled_upvars_ty().tuple_fields(),
context_before:             ty::Error(_) => Default::default(),
context_after:             ty::Infer(_) => panic!("upvar_tys called before capture types are inferred"),