syntax_data: {"ast_node_type":"other","tokens":[{"end":88,"kind":"keyword","start":0,"text":"Box::new(AggregateKind::Coroutine(closure_id.to_def_id(),"}]}
source_snippet:                         Box::new(AggregateKind::Coroutine(closure_id.to_def_id(), args))
context_before:                     UpvarArgs::Coroutine(args) => {
context_after:                     }