syntax_data: {"ast_node_type":"variable","tokens":[{"end":63,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let predicates = predicates.instantiate_own(tcx, args);
context_before:         assert_eq!(predicates.parent, None);
context_after:         let mut obligations = PredicateObligations::with_capacity(predicates.len());