syntax_data: {"ast_node_type":"other","tokens":[{"end":64,"kind":"keyword","start":0,"text":"ty::ExistentialPredicate::Trait(tr)"}]}
source_snippet:                         ty::ExistentialPredicate::Trait(tr) => {
context_before:                     self.bound_computation(predicate, |computation, predicate| match predicate {
context_after:                             computation.add_args(tr.args.as_slice())