{"ast_node_type":"enum","tokens":[{"end":96,"kind":"keyword","start":0,"text":"//!"}]}
//! except if the type has no constructors (like `enum Void {}` but not like `Result<!, !>`), we
//! `exhaustive_patterns` feature is turned on, in which case we do treat them as empty. And also
//! specifically allow `match void {}` to be exhaustive. There are additionally considerations of