private static String ToDotString(PredictionContext context)
{
StringBuilder nodes = new StringBuilder();
StringBuilder edges = new StringBuilder();
IDictionary <PredictionContext, PredictionContext> visited = new IdentityHashMap <PredictionContext, PredictionContext>();
IDictionary <PredictionContext, int> contextIds = new IdentityHashMap <PredictionContext, int>();
Stack <PredictionContext> workList = new Stack <PredictionContext>();
visited[context] = context;
contextIds[context] = contextIds.Count;
workList.Push(context);
while (workList.Count > 0)
{
PredictionContext current = workList.Pop();
nodes.Append(" s").Append(contextIds[current]).Append('[');
if (current.Size > 1)
{
nodes.Append("shape=record, ");
}
nodes.Append("label=\"");
if (current.IsEmpty)
{
nodes.Append(PredictionContext.IsEmptyLocal(current) ? '*' : '$');
}
else if (current.Size > 1)
{
for (int i = 0; i < current.Size; i++)
{
if (i > 0)
{
nodes.Append('|');
}
nodes.Append("<p").Append(i).Append('>');
if (current.GetReturnState(i) == PredictionContext.EmptyFullStateKey)
{
nodes.Append('$');
}
else if (current.GetReturnState(i) == PredictionContext.EmptyLocalStateKey)
{
nodes.Append('*');
}
}
}
else
{
nodes.Append(contextIds[current]);
}
nodes.AppendLine("\"];");
for (int i = 0; i < current.Size; i++)
{
if (current.GetReturnState(i) == PredictionContext.EmptyFullStateKey ||
current.GetReturnState(i) == PredictionContext.EmptyLocalStateKey)
{
continue;
}
if (!visited.ContainsKey(current.GetParent(i)))
{
visited[current.GetParent(i)] = current.GetParent(i);
contextIds[current.GetParent(i)] = contextIds.Count;
workList.Push(current.GetParent(i));
}
edges.Append(" s").Append(contextIds[current]);
if (current.Size > 1)
{
edges.Append(":p").Append(i);
}
edges.Append("->");
edges.Append('s').Append(contextIds[current.GetParent(i)]);
edges.Append("[label=\"").Append(current.GetReturnState(i)).Append("\"]");
edges.AppendLine(";");
}
}
StringBuilder builder = new StringBuilder();
builder.AppendLine("digraph G {");
builder.AppendLine("rankdir=LR;");
builder.Append(nodes);
builder.Append(edges);
builder.AppendLine("}");
return(builder.ToString());
}