syntax_data: {"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"Ok(ep_a.rebind(ty::ExistentialPredicate::Trait("}]}
source_snippet:                     Ok(ep_a.rebind(ty::ExistentialPredicate::Trait(
context_before:                 (ty::ExistentialPredicate::Trait(a), ty::ExistentialPredicate::Trait(b)) => {
context_after:                         relation.relate(ep_a.rebind(a), ep_b.rebind(b))?.skip_binder(),