public void GenerateContinuations()
{
foreach (var continuation in Key.Where(x => !x.IsFinished).GroupBy(x => x.NextPattern))
{
var key = new StateKey(continuation.Select(x => x.NextProduction), AllProductions);
Continuations.Add(continuation.Key, Machine.GetOrCreateNode(key));
}
var finished = Key.Where(x => x.IsFinished).ToArray();
if (finished.Length == 1)
{
CompletedProduction = finished[0];
}
else if (finished.Length > 1)
{
var maxValue = finished.Max(x => x.Precedence.Value);
var maxFinished = finished.Where(x => x.Precedence.Value == maxValue).ToArray();
if (maxFinished.Length == 1)
{
CompletedProduction = finished.OrderBy(x => x.Precedence.Value).First();
}
else
{
// TODO: better error message
throw new InvalidOperationException("Grammar is ambiguous");
}
}
}
public StateNode(StateKey Key, StateMachine machine, Dictionary <string, Production[]> allProductions)
{
this.Key = Key;
Continuations = new Dictionary <StackItemPattern, StateNode>();
Machine = machine;
AllProductions = allProductions;
}
public StateNode GetOrCreateNode(StateKey key)
{
if (!nodes.ContainsKey(key))
{
nodes[key] = new StateNode(key, this, AllProductions);
// DONT do this in the constructor: We need this item to exist in the dict before this is called.
nodes[key].GenerateContinuations();
}
return(nodes[key]);
}