public void TestEwahCompressedBitArray()
        {
            Console.WriteLine("testing EWAH (basic)");
            const long zero       = 0;
            const long specialval = 1L | (1L << 4) | (1L << 63);
            const long notzero    = ~zero;
            var        myarray1   = new EwahCompressedBitArray
            {
                zero, zero, zero, specialval, specialval, notzero, zero
            };

            Assert.AreEqual(myarray1.GetPositions().Count, 6 + 64);
            var myarray2 = new EwahCompressedBitArray();

            myarray2.Add(zero);
            myarray2.Add(specialval);
            myarray2.Add(specialval);
            myarray2.Add(notzero);
            myarray2.Add(zero);
            myarray2.Add(zero);
            myarray2.Add(zero);
            Assert.AreEqual(myarray2.GetPositions().Count, 6 + 64);
            List <int> data1     = myarray1.GetPositions();
            List <int> data2     = myarray2.GetPositions();
            var        logicalor = new List <int>();

            {
                var tmp = new HashSet <int>();
                tmp.AddRange(data1);
                tmp.AddRange(data2);
                logicalor.AddRange(tmp);
            }
            logicalor.Sort();
            var logicaland = new List <int>();

            logicaland.AddRange(data1);
            logicaland.Retain(data2);
            logicaland.Sort();
            EwahCompressedBitArray arrayand = myarray1.And(myarray2);

            AreEqual(arrayand.GetPositions(), logicaland);
            EwahCompressedBitArray arrayor = myarray1.Or(myarray2);

            AreEqual(arrayor.GetPositions(), logicalor);
            EwahCompressedBitArray arrayandbis = myarray2.And(myarray1);

            AreEqual(arrayandbis.GetPositions(), logicaland);
            EwahCompressedBitArray arrayorbis = myarray2.Or(myarray1);

            AreEqual(arrayorbis.GetPositions(), logicalor);
            var x = new EwahCompressedBitArray();

            foreach (int i in myarray1.GetPositions())
            {
                x.Set(i);
            }
            AreEqual(x.GetPositions(), myarray1.GetPositions());
            x = new EwahCompressedBitArray();
            foreach (int i in myarray2.GetPositions())
            {
                x.Set(i);
            }
            AreEqual(x.GetPositions(), myarray2.GetPositions());
            x = new EwahCompressedBitArray();
            foreach (int pos in myarray1)
            {
                x.Set(pos);
            }
            AreEqual(x.GetPositions(), myarray1.GetPositions());
            x = new EwahCompressedBitArray();
            foreach (int pos in myarray2)
            {
                x.Set(pos);
            }
            AreEqual(x.GetPositions(), myarray2.GetPositions());
            Console.WriteLine("testing EWAH (basic):ok");
        }