{"ast_node_type":"variable","tokens":[{"end":60,"kind":"keyword","start":0,"text":"if"}]}
                if let Ok(rhs) = src.clone().expect_leaf() {
            OpDelimited::Op(Op::Ident(lhs)) => {
                    if matches!(rhs, tt::Leaf::Ident(it) if it.sym == lhs.sym) {