public bool Equals(Tags tags)
{
return(_Id == tags._Id);
}
public DirectedEdge(Tags target)
{
Target = target;
Directionality = 0;
}
public void Add(Tags to)
{
Add(new DownwardEdge(From, to));
}
public DownwardEdges(Tags from)
{
From = from;
}
public DownwardEdge(Tags from, Tags to)
{
From = from;
To = to;
}
private static Tags?ToposortVisit(Dictionary <Tags, DownwardEdges> allEdges, Tags tag, bool isTopLevel, int[] result, Dictionary <int, bool> state, ref int nextIndex)
{
var id = tag.Id;
bool visiting;
if (state.TryGetValue(id, out visiting))
{
if (visiting)
{
if (Tracing)
{
Console.WriteLine("{0}Cycle @{1}", new string('.', Depth + 1), tag);
}
// HACK: Break this cycle.
return(tag);
}
else
{
return(null);
}
}
if (Tracing)
{
Console.WriteLine("{0}{1}", new string('.', Depth), tag);
}
Depth++;
state[id] = true;
bool aborted = false;
DownwardEdges downwardEdges;
Tags?cycle = null;
if (allEdges.TryGetValue(tag, out downwardEdges))
{
foreach (var edge in downwardEdges)
{
cycle = ToposortVisit(allEdges, edge.To, false, result, state, ref nextIndex);
// We hit a cycle, so we bail out.
if (cycle.HasValue)
{
if (state[id] == true)
{
state.Remove(id);
}
Depth--;
// We don't propagate the cycle, though.
return(null);
}
}
}
Assign(tag, result, state, ref nextIndex);
Depth--;
return(cycle);
}
