syntax_data: {"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:         if trait_pred.polarity == ty::PredicatePolarity::Negative {
context_before:         // that their args are WF.
context_after:             self.add_wf_preds_for_negative_trait_pred(trait_ref);