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// OrderedSequence.cs
//
// Authors:
// Alejandro Serrano "Serras" (trupill@yahoo.es)
// Marek Safar <marek.safar@gmail.com>
// Jb Evain <jbevain@novell.com>
//
// Copyright (C) 2007 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.
// Needed for NET30
#if !NET_4_6
using System.Collections.Generic;
namespace System.Linq.Reimplement
{
internal class OrderedSequence<TElement, TKey> : OrderedEnumerable<TElement>
{
private readonly IComparer<TKey> _comparer;
private readonly SortDirection _direction;
private readonly OrderedEnumerable<TElement> _parent;
private readonly Func<TElement, TKey> _selector;
internal OrderedSequence(IEnumerable<TElement> source, Func<TElement, TKey> keySelector, IComparer<TKey> comparer, SortDirection direction)
: base(source)
{
_selector = keySelector;
_comparer = comparer ?? Comparer<TKey>.Default;
_direction = direction;
}
internal OrderedSequence(OrderedEnumerable<TElement> parent, IEnumerable<TElement> source, Func<TElement, TKey> keySelector, IComparer<TKey> comparer, SortDirection direction)
: this(source, keySelector, comparer, direction)
{
_parent = parent;
}
public override SortContext<TElement> CreateContext(SortContext<TElement> current)
{
SortContext<TElement> context = new SortSequenceContext<TElement, TKey>(_selector, _comparer, _direction, current);
if (_parent != null)
{
return _parent.CreateContext(context);
}
return context;
}
protected override IEnumerable<TElement> Sort(IEnumerable<TElement> source)
{
return QuickSort<TElement>.Sort(source, CreateContext(null));
}
}
}
#endif