syntax_data: {"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"for"}]}
source_snippet:                         for upvar in args.as_coroutine_closure().upvar_tys() {
context_before:                     ty::CoroutineClosure(_, args) => {
context_after:                             queue_type(self, upvar);