private DFAState <T> CalculateDfaState(RegEx <T> regEx)
{
if (dictionaryOfDfaStates.ContainsKey(regEx))
{
return(dictionaryOfDfaStates[regEx]); //return this state
}
var new_state = new DFAState <T>();
dictionaryOfDfaStates.Add(regEx, new_state);
var listOfTransitions = new List <KeyValuePair <T, DFAState <T> > >();
foreach (var c in regEx.DerivChanges())
{
listOfTransitions.Add(new KeyValuePair <T, DFAState <T> >(c, CalculateDfaState(regEx.Derivative(c))));
}
if (regEx.HasEpsilon())
{
new_state._accepting = accepting;
}
else
{
new_state._accepting = 0;
}
if (listOfTransitions.Count == 0 || !listOfTransitions[0].Key.Equals(MinSymbol <T>()))
{
if (deadState == null)
{
deadState = new DFAState <T>();
deadState._accepting = 0;
deadState._transitions = new KeyValuePair <T, DFAState <T> >[] { new KeyValuePair <T, DFAState <T> >(MinSymbol <T>(), deadState) };
}
listOfTransitions.Insert(0, new KeyValuePair <T, DFAState <T> >(MinSymbol <T>(), deadState));
for (int i = 1; i < listOfTransitions.Count; i++)
{
if (listOfTransitions[i - 1].Key.CompareTo(listOfTransitions[i].Key) >= 0)
{
throw new Exception("Inpropper order");
}
}
}
new_state._transitions = listOfTransitions.ToArray();
return(new_state);
}
/// <summary>
/// Create RegExDfa from RegEx
/// </summary>
/// <param name="regEx">Regular Expression from which is made automata</param>
/// <param name="acceptingStateMarker">Number for accepting states</param>
public RegExDfa(RegEx <T> regEx, uint acceptingStateMarker)
{
accepting = acceptingStateMarker;
_start = CalculateDfaState(regEx);
}
/// <summary>
/// Create RegExDfa with start state
/// </summary>
/// <param name="start">Start state</param>
public RegExDfa(DFAState <T> start)
{
_start = start;
}