EventStore.Core.Index.PTable.LocateRecordRange C# (CSharp) Method

        private Range LocateRecordRange(IndexEntryKey key)
        {
            var midpoints = _midpoints;
            if (midpoints == null)
                return new Range(0, Count - 1);
            long lowerMidpoint = LowerMidpointBound(midpoints, key);
            long upperMidpoint = UpperMidpointBound(midpoints, key);
            return new Range(midpoints[lowerMidpoint].ItemIndex, midpoints[upperMidpoint].ItemIndex);
        }