syntax_data: {"ast_node_type":"variable","tokens":[{"end":44,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let coroutine_state_def_id =
context_before:             CoroutineKind::Coroutine(_) => {
context_after:                     self.tcx.require_lang_item(LangItem::CoroutineState, source_info.span);