class PromQLEngine {

    public Query newRangeQuery(String qs, Instant start, Instant end, Duration interval) {
        Expr expr = Parser.parseExpr(qs);
        if (expr.type() != ValueType.vector && expr.type() != ValueType.scalar) {
            throw new IllegalStateException(String.format(
                "invalid expression type %s for range query, must be Scalar or instant Vector",
                typeString(expr.type())));
        }
        Query qry = newQuery(expr, start, end, interval);
        qry.setQ(qs);
        return qry;
    }

    public  PromQLEngine(Storage storage);
    public  PromQLEngine(Storage storage, EngineOptions options);

}