public static TemporalIntervalRelation GetTemporalIntervalRelation(this SmallDateInterval x, SmallDateInterval y)
    {
        TemporalIntervalRelation relation;

        if (x.Precedes(y))
        {
            relation = TemporalIntervalRelation.Precedes;
        }
        else if (x.Meets(y))
        {
            relation = TemporalIntervalRelation.Meets;
        }
        else if (x.OverlapsWith(y))
        {
            relation = TemporalIntervalRelation.OverlapsWith;
        }
        else if (x.Starts(y))
        {
            relation = TemporalIntervalRelation.Starts;
        }
        else if (x.During(y))
        {
            relation = TemporalIntervalRelation.During;
        }
        else if (x.Finishes(y))
        {
            relation = TemporalIntervalRelation.Finishes;
        }
        else if (x.IsPrecededBy(y))
        {
            relation = TemporalIntervalRelation.IsPrecededBy;
        }
        else if (x.IsMetBy(y))
        {
            relation = TemporalIntervalRelation.IsMetBy;
        }
        else if (x.IsOverlappedBy(y))
        {
            relation = TemporalIntervalRelation.IsOverlappedBy;
        }
        else if (x.IsStartedBy(y))
        {
            relation = TemporalIntervalRelation.IsStartedBy;
        }
        else if (Contains(x, y))
        {
            relation = TemporalIntervalRelation.Contains;
        }
        else if (x.IsFinishedBy(y))
        {
            relation = TemporalIntervalRelation.IsFinishedBy;
        }
        else if (x.IsEqualTo(y))
        {
            relation = TemporalIntervalRelation.IsEqualTo;
        }
        else
        {
            throw new InvalidOperationException();
        }

        return(relation);
    }
 public static bool IsMetBy(this SmallDateInterval x, SmallDateInterval y) => y.Meets(x);