public bool Equals(Lr0State i)
{
if ((System.Object)i == null)
{
return false;
}
if (itemSet.Count != i.itemSet.Count)
return false;
bool result = true;
foreach (var item in i.itemSet)
{
result = result && itemSet.Contains(item);
}
return result;
}
public static Lr0State Closure(Lr0State theState, List<GrammarRule> theGrammar)
{
Lr0State ResultState = new Lr0State(theState.itemSet);
bool hasChanged = false;
do
{
hasChanged = false;
List<Item> forwardItems = theState.GetForwardItems();
foreach (Item theItem in forwardItems)
{
Symbol currentSymbol = theItem.getCurrentSymbol();
List<Item> theProductions = Lr0GenerationHelper.getItemsById(currentSymbol.id, theGrammar);
foreach (var item in theProductions)
{
hasChanged = theState.Add(item) || hasChanged;
}
}
} while (hasChanged);
return ResultState;
}
public static DFA BuildLr0(List<GrammarRule> AugmentedGrammar, out HashSet<Tuple<dfaState, Symbol, Int32>> ReduceStates, out HashSet<input> Tokens)
{
Tokens = new HashSet<input>();
ReduceStates = new HashSet<Tuple<dfaState, Symbol, Int32>>();
DFA E = new DFA();
E.start = 0;
List<Lr0State> T = new List<Lr0State>();
GrammarRule FirstProduction = AugmentedGrammar[0];
Lr0State InitialState = new Lr0State();
InitialState.Add(new Item(FirstProduction));
InitialState = Closure(InitialState, AugmentedGrammar);
T.Add(InitialState);
bool hasChanged = false;
do
{
hasChanged = false;
List<Lr0State> tempState = new List<Lr0State>();
foreach (Lr0State s in T)
{
tempState.Add(s);
}
foreach (Lr0State I in tempState)
{
foreach (Item item in I.itemSet)
{
if (!item.isFinal())
{
Symbol X = item.getCurrentSymbol();
if (X.id != "úEndSymbol")
{
Lr0State J = Goto(I, X, AugmentedGrammar);
int JIndex = -1;
if (T.Contains(J))
{
JIndex = T.IndexOf(J);
}
else
{
hasChanged = true;
T.Add(J);
JIndex = T.IndexOf(J);
}
if (item.getNextSymbol() != null)
if (item.getNextSymbol().id == "úEndSymbol")
E.final.Add(JIndex);
int Iindex = T.IndexOf(I);
string TransitionSymbol = X.id;
Tokens.Add(TransitionSymbol);
if (!E.transitionTable.ContainsKey(new KeyValuePair<int, string>(Iindex, TransitionSymbol)))
E.transitionTable.Add(new KeyValuePair<int, string>(Iindex, TransitionSymbol), JIndex);
}
}
else
{
HashSet<Symbol> followSet = Follow(item.Rule.RuleSymbol, AugmentedGrammar);
foreach (Symbol x in followSet)
{
ReduceStates.Add(new Tuple<dfaState, Symbol, Int32>(T.IndexOf(I), x, AugmentedGrammar.IndexOf(item.Rule)));
}
}
}
}
} while (hasChanged);
return E;
}
public static Lr0State Goto(Lr0State theState, Symbol inputSymbol, List<GrammarRule> theGrammar)
{
List<Item> generatedItems = theState.GetGotoItems(inputSymbol);
Lr0State resultState = new Lr0State(generatedItems);
return Closure(resultState, theGrammar);
}
