{"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"//"}]}
        // but as a parenthesized list. This (and likely `MetaItem`) should be changed in
        // FIXME: This parses `unsafe()` not as unsafe attribute syntax in `MetaItem`,
        // such a way that builtin macros don't accept extraneous `unsafe()`.