syntax_data: {"ast_node_type":"other","tokens":[{"end":36,"kind":"keyword","start":0,"text":"ty::ClosureKind::FnOnce,"}]}
source_snippet:             ty::ClosureKind::FnOnce,
context_before:             coroutine_def_id.to_def_id(),
context_after:             tcx.lifetimes.re_erased,