{"ast_node_type":"other","tokens":[{"end":39,"kind":"keyword","start":0,"text":"///"}]}
    /// * `#[doc(...)]` returns `None`.
    /// * `#[doc = "doc"]` returns `Some(("doc", CommentKind::Line))`.
    fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)>;