private bool AddClosureItems(ParserState state)
{
bool result = false;
for (int i = 0; i < state.Items.Count; i++)
{
LRItem item = state.Items[i];
NonTerminal nextNT = item.Core.NextElement as NonTerminal;
if (nextNT == null)
{
continue;
}
foreach (Production prod in nextNT.Productions)
{
LR0Item core = prod.LR0Items[0];
LRItem newItem = TryFindItem(state, core);
if (newItem == null)
{
newItem = new LRItem(state, core);
state.Items.Add(newItem);
result = true;
}
newItem.NewLookaheads.AddRange(item.Core.TailFirsts);
if (item.Core.TailIsNullable && !item.PropagateTargets.Contains(newItem))
{
item.PropagateTargets.Add(newItem);
}
}
}
return(result);
}
private void CreateParserStates()
{
_data.States.Clear();
_stateHash = new ParserStateTable();
CreateInitialAndFinalStates();
string augmRootKey = _data.AugmentedRoot.Key;
for (int index = 0; index < _data.States.Count; index++)
{
ParserState state = _data.States[index];
AddClosureItems(state);
Dictionary <string, LR0ItemList> shiftTable = GetStateShifts(state);
foreach (string input in shiftTable.Keys)
{
LR0ItemList shiftedCoreItems = shiftTable[input];
ParserState newState = FindOrCreateState(shiftedCoreItems);
state.Actions[input] = new ActionRecord(input, ParserActionType.Shift, newState, null);
foreach (LR0Item coreItem in shiftedCoreItems)
{
LRItem fromItem = FindItem(state, coreItem.Production, coreItem.Position - 1);
LRItem toItem = FindItem(newState, coreItem.Production, coreItem.Position);
if (!fromItem.PropagateTargets.Contains(toItem))
{
fromItem.PropagateTargets.Add(toItem);
}
}
}
}
_data.FinalState = _data.InitialState.Actions[_data.AugmentedRoot.Key].NewState;
}
private bool AddClosureItems(ParserState state)
{
bool result = false;
for (int i = 0; i < state.Items.Count; i++)
{
LRItem item = state.Items[i];
NonTerminal nextNT = item.Core.NextElement as NonTerminal;
if (nextNT == null) continue;
foreach (Production prod in nextNT.Productions)
{
LR0Item core = prod.LR0Items[0];
LRItem newItem = TryFindItem(state, core);
if (newItem == null)
{
newItem = new LRItem(state, core);
state.Items.Add(newItem);
result = true;
}
newItem.NewLookaheads.AddRange(item.Core.TailFirsts);
if (item.Core.TailIsNullable && !item.PropagateTargets.Contains(newItem))
item.PropagateTargets.Add(newItem);
}
}
return result;
}