{"ast_node_type":"other","tokens":[{"end":20,"kind":"keyword","start":0,"text":"pub"}]}
    pub pat: P<Pat>,
    /// Match arm pattern, e.g. `10` in `match foo { 10 => {}, _ => {} }`.
    /// Match arm guard, e.g. `n > 10` in `match foo { n if n > 10 => {}, _ => {} }`.