// Invariant: a[i] < a[i+1] for i > item
// returns flase is head of the list was moved & as a result consistancy of list depends on head consistancy.
private bool SiftItem(int item)
{
Debug.Assert(firstNotEmpty <= item && item < arr.Length);
ResettableIterator it = arr[item];
while (item + 1 < arr.Length)
{
ResettableIterator itNext = arr[item + 1];
Debug.Assert(it.Current != null && itNext.Current != null);
XmlNodeOrder order = Query.CompareNodes(it.Current, itNext.Current);
if (order == XmlNodeOrder.Before)
{
break;
}
if (order == XmlNodeOrder.After)
{
arr[item] = itNext;
//arr[item + 1] = it;
item++;
}
else
{ // Same
arr[item] = it;
if (!Advance(item))
{
return(false);
}
it = arr[item];
}
}
arr[item] = it;
return(true);
}
// returns false is iterator at pos reached it's end & as a result head of the array may be moved
private bool Advance(int pos)
{
if (!arr[pos].MoveNext())
{
if (firstNotEmpty != pos)
{
ResettableIterator empty = arr[pos];
Array.Copy(arr, firstNotEmpty, arr, firstNotEmpty + 1, pos - firstNotEmpty);
arr[firstNotEmpty] = empty;
}
firstNotEmpty++;
return(false);
}
return(true);
}
protected ResettableIterator(ResettableIterator other)
{
base.count = other.count;
}