{"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"CfgExpr::Atom(atom)"}]}
                CfgExpr::Atom(atom) => Self { negate: true, var: Some(atom) },
                CfgExpr::Invalid => Self { negate: true, var: None },
                _ => unreachable!("non-atom {:?}", expr),