protected SortContext(SortDirection direction, SortContext <TElement> child_context)
{
this.direction = direction;
this.child_context = child_context;
}
public abstract SortContext <TElement> CreateContext(SortContext <TElement> current);
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;
}