Initial Commit

Common/Auxiliary/IEnumerableExtensions.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Collections;
+
+namespace Microsoft.Research.DynamicDataDisplay.Common.Auxiliary
+{
+	internal static class IEnumerableExtensions
+	{
+		public static bool CountGreaterOrEqual<T>(this IEnumerable<T> enumerable, int count)
+		{
+			int counter = 0;
+			using (var enumerator = enumerable.GetEnumerator())
+			{
+				while (counter < count && enumerator.MoveNext())
+				{
+					counter++;
+				}
+			}
+
+			return counter == count;
+		}
+
+		public static IEnumerable<IEnumerable<T>> Split<T>(this IEnumerable<T> source, int maxCount)
+		{
+			using (var enumerator = new FixedEnumeratorWrapper<T>(source.GetEnumerator()))
+			{
+				do
+				{
+					var enumerable = new FixedEnumerable<T>(enumerator);
+					yield return enumerable.Take(maxCount);
+				}
+				while (enumerator.CanMoveNext);
+			}
+		}
+
+		private sealed class FixedEnumeratorWrapper<T> : IEnumerator<T>
+		{
+			private readonly IEnumerator<T> enumerator;
+
+			public FixedEnumeratorWrapper(IEnumerator<T> enumerator)
+			{
+				this.enumerator = enumerator;
+			}
+
+			#region IEnumerator<T> Members
+
+			public T Current
+			{
+				get { return enumerator.Current; }
+			}
+
+			#endregion
+
+			#region IDisposable Members
+
+			public void Dispose()
+			{
+				//enumerator.Dispose();
+			}
+
+			#endregion
+
+			#region IEnumerator Members
+
+			object IEnumerator.Current
+			{
+				get { throw new NotImplementedException(); }
+			}
+
+			private bool canMoveNext = false;
+			public bool CanMoveNext
+			{
+				get { return canMoveNext; }
+			}
+
+			public bool MoveNext()
+			{
+				canMoveNext = enumerator.MoveNext();
+				return canMoveNext;
+			}
+
+			public void Reset()
+			{
+				enumerator.Reset();
+			}
+
+			#endregion
+		}
+
+		private sealed class FixedEnumerable<T> : IEnumerable<T>
+		{
+			private readonly IEnumerator<T> enumerator;
+			public FixedEnumerable(IEnumerator<T> enumerator)
+			{
+				this.enumerator = enumerator;
+			}
+
+			#region IEnumerable<T> Members
+
+			public IEnumerator<T> GetEnumerator()
+			{
+				return enumerator;
+			}
+
+			#endregion
+
+			#region IEnumerable Members
+
+			IEnumerator IEnumerable.GetEnumerator()
+			{
+				throw new NotSupportedException();
+			}
+
+			#endregion
+		}
+	}
+}