private TreePredictableItem(TreePredictableItem <TNode> parent, TNode node)
{
_parent = parent;
_node = node;
_count = node.Count;
_isReal = true;
}
internal static IEnumerable <IEnumerable <TNode> > FindOrderedItems(IEnumerable <TNode> database)
{
var seedEnumerator = database.GetEnumerator();
if (seedEnumerator.MoveNext())
{
var seedItem = new TreePredictableItem <TNode>(null, seedEnumerator);
var queue = new List <TreePredictableItem <TNode> > {
seedItem
};
while (queue.Count != 0)
{
var item = queue[0];
queue.RemoveAt(0);
if (item._isReal)
{
yield return(item);
if (item._enumerator.MoveNext())
{
var nextItem = new TreePredictableItem <TNode>(item._parent, item._enumerator);
nextItem.Enqueue(queue);
}
else
{
item._enumerator.Dispose();
}
if (1 < item._count)
{
item.MakePotential();
item.Enqueue(queue);
}
}
else
{
item.ExpandPotentialParent(queue);
}
}
}
}
internal static void PrototypeTreePredictions(ScoredTokenPredictionMaker maker,
StringTokens tokens,
int maxCount)
{
string ToText(TokenPredictorInfo info)
{
var text = tokens[info.Token];
var nullIndex = text.IndexOf('\0');
if (nullIndex != -1)
{
text = text.Substring(0, nullIndex);
}
return(text);
}
var roots = maker.GetContextRoots();
Debug.WriteLine(string.Empty);
Debug.WriteLine("Prototype tree prediction:");
var enumerable = TreePredictableItem <TokenPredictorInfo> .FindOrderedItems(roots.SortedEnumerable);
using (var enumerator = enumerable.GetEnumerator())
{
for (var count = 0; count < maxCount && enumerator.MoveNext(); count++)
{
var text = string.Empty;
foreach (var info in enumerator.Current)
{
text += $"{ToText(info)} ";
}
Debug.WriteLine(text);
}
}
Debug.WriteLine(string.Empty);
}
private void ExpandPotentialParent(List <TreePredictableItem <TNode> > queue)
{
var item = this;
var done = false;
while (!done)
{
var node = item._node;
var enumerator = node.GetChildren().GetEnumerator();
if (enumerator.MoveNext())
{
var firstNode = enumerator.Current;
if (enumerator.MoveNext())
{
item = new TreePredictableItem <TNode>(item, enumerator);
item.Enqueue(queue);
done = true;
}
else
{
// Walking down single branch.
enumerator.Dispose();
item = new TreePredictableItem <TNode>(item, firstNode);
}
}
else
{
// No potential next node.
enumerator.Dispose();
done = true;
}
}
}
internal TreePredictableItem(TreePredictableItem <TNode> parent, IEnumerator <TNode> enumerator)
: this(parent, enumerator.Current)
{
_enumerator = enumerator;
}