private IEnumerable <IReduceInput <T> > GetTerminalInputsAfterPredicate(INonTerminalPredicate <T> NonTerminal)
{
ISituationEdge <T> edge;
ProcessingQueue <ISituationEdge <T>, IReduceInput <T> > queue;
//IInput<T> input;
queue = new ProcessingQueue <ISituationEdge <T>, IReduceInput <T> >();
// add edges next to current non terminal
edge = GetEdge(NonTerminal);
queue.AddRange(edge.TargetNode.Edges);
// search for left recursive rules referenced by non terminal
foreach (SituationEdge <T> developpedEdge in DevelopRuleInputEdges(NonTerminal.Name))
{
// left recursive rule case
if ((developpedEdge.Predicate is INonTerminalPredicate <T> recursiveNonTerminal) && (recursiveNonTerminal.Name == NonTerminal.Name))
{
queue.AddRange(developpedEdge.TargetNode.Edges);
}
}
// search for loops
foreach (SituationEdge <T> developpedEdge in DevelopRuleInputEdges(NonTerminal.Name))
{
queue.AddRange(GetLoopedEdges(developpedEdge.TargetNode));
}
queue.Process((q, item) =>
{
foreach (IInput <T> input in item.Predicate.GetInputs())
{
if (input is IReduceInput <T> terminalInput)
{
q.AddResult(terminalInput);
}
//else if (item.Predicate is IReducePredicate<T>) q.AddResult(new EOSInput<T>());
else if (input is INonTerminalInput <T> nonTerminalInput)
{
q.AddRange(DevelopRuleInputEdges(nonTerminalInput.Name));
}
}
});
return(queue.Results);
}
public ISituationCollection <T> Develop(IEnumerable <ISituation <T> > Situations)
{
SituationCollection <T> developpedSituations;
Situation <T> newSituation;
IReduceInput <T>[] inputs;
ProcessingQueue <ISituation <T>, ISituation <T> > processingQueue;
//bool isReductionSituationAfterPredicate;
processingQueue = new ProcessingQueue <ISituation <T>, ISituation <T> >();
processingQueue.AddRange(Situations);
processingQueue.Process((q, situation) =>
{
q.AddResult(situation);
if (!(situation.Predicate is INonTerminalPredicate <T> nonTerminal))
{
return;
}
//isReductionSituationAfterPredicate = IsReductionStuationAfterPredicate(nonTerminal);
inputs = GetTerminalInputsAfterPredicate(nonTerminal).ToArray();
foreach (SituationEdge <T> developpedEdge in DevelopRuleInputEdges(nonTerminal.Name))
{
// basic case
foreach (IReduceInput <T> input in inputs)
{
newSituation = new Situation <T>(developpedEdge.Rule, developpedEdge.Predicate, input);
q.AddResult(newSituation);
}
}
});
developpedSituations = new SituationCollection <T>();
developpedSituations.AddRange(processingQueue.Results);
return(developpedSituations);
}