syntax_data: {"ast_node_type":"other","tokens":[{"end":40,"kind":"keyword","start":0,"text":"candidate:"}]}
source_snippet:     candidate: PolyTraitPredicate<'tcx>,
context_before:     obligation: &PolyTraitObligation<'tcx>,
context_after: ) -> PolyTraitPredicate<'tcx> {