private static IOrderedDataProducer <TSource> ThenBy <TSource, TKey>(IOrderedDataProducer <TSource> source, DotNet20.Func <TSource, TKey> selector, IComparer <TKey> comparer, bool descending)
{
comparer.ThrowIfNull("comparer");
IComparer <TSource> itemComparer = new ProjectionComparer <TSource, TKey>(selector, comparer);
if (descending)
{
itemComparer = itemComparer.Reverse();
}
itemComparer = new LinkedComparer <TSource>(source.Comparer, itemComparer);
return(new OrderedDataProducer <TSource>(source, itemComparer));
}
/// <summary>
/// Further orders the values from an ordered data-source by a transform on each term, descending
/// (the sort operation is only applied once for the combined ordering)
/// </summary>
/// <param name="source">The original data-producer and ordering</param>
/// <param name="selector">Returns the value (for each term) by which to order the sequence</param>
/// <param name="comparer">Comparer to compare the selected values</param>
/// <returns>A data-producer that yeilds the sequence ordered
/// by the selected value</returns>
/// <remarks>This will force all data to be buffered</remarks>
public static IOrderedDataProducer <TSource> ThenByDescending <TSource, TKey>(this IOrderedDataProducer <TSource> source, DotNet20.Func <TSource, TKey> selector, IComparer <TKey> comparer)
{
return(ThenBy(source, selector, comparer, true));
}
/// <summary>
/// Further orders the values from an ordered data-source by a transform on each term, descending
/// (the sort operation is only applied once for the combined ordering)
/// </summary>
/// <param name="source">The original data-producer and ordering</param>
/// <param name="selector">Returns the value (for each term) by which to order the sequence</param>
/// <returns>A data-producer that yeilds the sequence ordered
/// by the selected value</returns>
/// <remarks>This will force all data to be buffered</remarks>
public static IOrderedDataProducer <TSource> ThenByDescending <TSource, TKey>(this IOrderedDataProducer <TSource> source, Func <TSource, TKey> selector)
{
return(ThenBy(source, selector, Comparer <TKey> .Default, true));
}
/// <summary>
/// Further orders the values from an ordered data-source by a transform on each term, ascending
/// (the sort operation is only applied once for the combined ordering)
/// </summary>
/// <param name="source">The original data-producer and ordering</param>
/// <param name="selector">Returns the value (for each term) by which to order the sequence</param>
/// <returns>A data-producer that yeilds the sequence ordered
/// by the selected value</returns>
/// <remarks>This will force all data to be buffered</remarks>
public static IOrderedDataProducer <TSource> ThenBy <TSource, TKey>(this IOrderedDataProducer <TSource> source, DotNet20.Func <TSource, TKey> selector)
{
return(ThenBy(source, selector, Comparer <TKey> .Default, false));
}
/// <summary>
/// Further orders the values from an ordered data-source by a transform on each term, ascending
/// (the sort operation is only applied once for the combined ordering)
/// </summary>
/// <param name="source">The original data-producer and ordering</param>
/// <param name="selector">Returns the value (for each term) by which to order the sequence</param>
/// <param name="comparer">Comparer to compare the selected values</param>
/// <returns>A data-producer that yeilds the sequence ordered
/// by the selected value</returns>
/// <remarks>This will force all data to be buffered</remarks>
public static IOrderedDataProducer <TSource> ThenBy <TSource, TKey>(this IOrderedDataProducer <TSource> source, Func <TSource, TKey> selector, IComparer <TKey> comparer)
{
return(ThenBy(source, selector, comparer, false));
}
