public void Add(State current, char character, State next)
{
if (wrappedUp)
throw new InvalidOperationException("Table is wrapped up.");
List<State> nextStates;
var key = new Tuple<State, char>(current, character);
bool transitionExists = transitions.TryGetValue(key, out nextStates);
if (!transitionExists)
{
nextStates = new List<State>();
transitions.Add(key, nextStates);
}
bool duplicate = nextStates.Contains(next);
if (duplicate)
throw new InvalidOperationException("Transition is duplicated.");
nextStates.Add(next);
}
public IEnumerable<State> GetInitialEpsilonClosure(State initial)
{
var initialStateArray = new[] { initial };
return EpsilonClosure(initialStateArray);
}
private IEnumerable<State> GetNextStatesOfSingleState(State current, char character)
{
List<State> nextStates;
var key = new Tuple<State, char>(current, character);
IEnumerable<State> output;
bool transitionIsDefined = transitions.TryGetValue(key, out nextStates);
if (transitionIsDefined)
output = nextStates;
else
output = Enumerable.Empty<State>();
foreach (State state in output)
yield return state;
}
public IEnumerable<State> GetNextStates(State state, char character)
{
var nextStates = GetNextStatesOfSingleState(state, character);
var closure = EpsilonClosure(nextStates);
foreach (State nextState in closure)
yield return nextState;
}