class Range implements AutoCloseable {

    @Transient
    public Object getSingleValue()
    {
        if (!isSingleValue()) {
            throw new IllegalStateException("Range does not have just a single value");
        }
        return low.getValue();
    }

    @JsonCreator public  Range(
            @JsonProperty("low") Marker low,
            @JsonProperty("high") Marker high);

}