/// <summary>
/// Compiles the given AST <code>ast</code> into a oWFN petri net
/// </summary>
/// <exception cref="System.NullReferenceException">Thrown when the AST <c>ast</c> is null</exception>
/// <returns>An equivalent <c>PetriNet</c> representation</returns>
public PetriNet Compile()
{
if (this.ast == null)
{
throw new NullReferenceException("AST cannot be null");
}
// Phylum
net = new PetriNet();
String prefix = net.ActivityCount + ".internal.";
Place p1 = net.NewPlace(prefix + "initialized");
Place p2 = net.NewPlace(prefix + "closed");
// Initial Marking
p1.Tokens = 1;
// Final Marking
HashSet <Place> final = new HashSet <Place>();
final.Add(p2);
net.AddFinalSet(final);
// Compile inner activities
int newID = ++net.ActivityCount;
net = ast.Compile(net);
// Merge final net
net.Merge(p1, newID + ".internal.initialized");
net.Merge(p2, newID + ".internal.closed");
return(net);
}
