2008-05-01 Jb Evain <jbevain@novell.com>

	* SortDirection.cs, SortContext.cs, SortSequenceContext.cs:
	new infrastructure files for nested orderby/thenby calls.
	* QuickSort.cs: refactored out of OrderedSequence.cs
	* OrderedEnumerable.cs, OrderedSequence.cs: refactoring
	to use the new SortContext infrastructure.

svn path=/trunk/mcs/; revision=102297

1 files changed, 68 insertions, 0 deletions

diff --git a/mcs/class/System.Core/System.Linq/SortSequenceContext.cs b/mcs/class/System.Core/System.Linq/SortSequenceContext.cs
new file mode 100644
index 00000000000..67fd2b3c417
--- /dev/null
+++ b/mcs/class/System.Core/System.Linq/SortSequenceContext.cs
@@ -0,0 +1,68 @@
+//
+// SortSequenceContext.cs
+//
+// Author:
+//   Jb Evain (jbevain@novell.com)
+//
+// (C) 2008 Novell, Inc. (http://www.novell.com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+
+namespace System.Linq {
+
+	class SortSequenceContext<TElement, TKey> : SortContext<TElement> {
+
+		Func<TElement, TKey> selector;
+		IComparer<TKey> comparer;
+
+		TKey [] keys;
+
+		public SortSequenceContext (Func<TElement, TKey> selector, IComparer<TKey> comparer, SortDirection direction, SortContext<TElement> child_context)
+			: base (direction, child_context)
+		{
+			this.selector = selector;
+			this.comparer = comparer;
+		}
+
+		public override void Initialize (TElement [] elements)
+		{
+			if (child_context != null)
+				child_context.Initialize (elements);
+
+			keys = new TKey [elements.Length];
+			for (int i = 0; i < keys.Length; i++)
+				keys [i] = selector (elements [i]);
+		}
+
+		public override int Compare (int first_index, int second_index)
+		{
+			int comparison = comparer.Compare (keys [first_index], keys [second_index]);
+
+			if (comparison == 0 && child_context != null)
+				comparison = child_context.Compare (first_index, second_index);
+
+			return direction == SortDirection.Descending ? -comparison : comparison;
+		}
+	}
+}