{"ast_node_type":"variable","tokens":[{"end":100,"kind":"keyword","start":0,"text":"let"}]}
        let mut fields: SmallVec<[_; 2]> = (0..other_ctor_arity).map(|_| PatOrWild::Wild).collect();
        // Start with a slice of wildcards of the appropriate length.
        // Fill `fields` with our fields. The arities are known to be compatible.