{"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":")"}]}
    ) -> PResult<'a, (AttrVec, P<Block>)> {
        loop_header: Option<Span>,
        if let Some(block) = self.eat_metavar_seq(MetaVarKind::Block, |this| this.parse_block()) {