syntax_data: {"ast_node_type":"other","tokens":[{"end":62,"kind":"keyword","start":0,"text":"preds:"}]}
source_snippet:         preds: &'tcx List<ty::PolyExistentialPredicate<'tcx>>,
context_before:         interner: TyCtxt<'tcx>,
context_after:         region: ty::Region<'tcx>,