{"ast_node_type":"variable","tokens":[{"end":64,"kind":"keyword","start":0,"text":"if"}]}
        if let ExprKind::Unary(UnOp::Neg, ref inner) = expr.kind
        // even if there are 3 or more negations
            && let ExprKind::Unary(UnOp::Neg, ref inner2) = inner.kind