{"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"ty::Adt(..)"}]}
                ty::Adt(..) if ty.is_box() => Some("`Box` must be non-null".into()),
                ty::Ref(..) => Some("references must be non-null".into()),
                ty::FnPtr(..) => Some("function pointers must be non-null".into()),