syntax_data: {"ast_node_type":"other","tokens":[{"end":92,"kind":"keyword","start":0,"text":"ty::FnDef(def_id,"}]}
source_snippet:         ty::FnDef(def_id, _) | ty::Closure(def_id, _) | ty::CoroutineClosure(def_id, _) => {
context_before:         ty::Ref(_, _, mutbl) => Some(SimplifiedType::Ref(mutbl)),
context_after:             Some(SimplifiedType::Closure(def_id))