private void EarleyReducer(EarleyItem completed, int setNumber)
{
int position = completed.GetOrignPosition();
EarleySet set = Sets[position];
List <EarleyItem> items = set.GetEarleyItemList();
for (int j = 0; j < items.Count; j++)
{
EarleyItem current = items[j];
Symbol next = current.GetCurrentNextSymbol();
if (next != null && next.Equals(completed.GetRule().GetLeftHandSideOfRule()))
{
EarleyItem newEarleyItem = new EarleyItem(
setNumber,
new DottedRule(current.GetRule(), current.GetRulePosition() + 1),
current.GetOrignPosition()
);
if (current.GetCurrentPrevSymbolList() != null && current.GetCurrentPrevSymbolList().Count > 0)
{
newEarleyItem.AddPredecessorLink(current, position);
}
newEarleyItem.AddReducerLink(completed, position);
AddToSet(newEarleyItem, setNumber, "EarleyReducer");
}
}
}
private bool LeoReducer(EarleyItem completed, int setNumber)
{
int position = completed.GetOrignPosition();
Symbol lhs = completed.GetRule().GetLeftHandSideOfRule();
EarleySet set = Sets[position];
LeoItem transitiveItem = set.FindLeoItemBySymbol(lhs);
if (transitiveItem == null)
{
return(false);
}
EarleyItem newEarleyItem = new EarleyItem(
setNumber,
transitiveItem.GetDottedRule(),
transitiveItem.GetOrignPosition()
);
EarleyItem current = Sets[transitiveItem.GetOrignPosition()].GetEarleyItemList()
.Find(el => el.GetDottedRule().Equals(transitiveItem.GetDottedRule()) && el.GetOrignPosition() == transitiveItem.GetOrignPosition());
if (current.GetCurrentPrevSymbolList() != null && current.GetCurrentPrevSymbolList().Count > 0)
{
newEarleyItem.AddPredecessorLink(current, position);
}
newEarleyItem.AddReducerLink(completed, position);
AddToSet(
newEarleyItem,
setNumber,
"LeoReducer"
);
return(true);
}
private void Scanner(EarleyItem current, int setNumber, Char inputSymbol)
{
Symbol nextSymbol = current.GetCurrentNextSymbol();
if (nextSymbol != null && nextSymbol.Equals(inputSymbol.ToString()))
{
EarleyItem newEarleyItem = new EarleyItem(
setNumber + 1,
new DottedRule(current.GetRule(), current.GetRulePosition() + 1),
current.GetOrignPosition()
);
if (newEarleyItem.GetCurrentPrevSymbolList() != null && newEarleyItem.GetCurrentPrevSymbolList().Count > 0)
{
newEarleyItem.AddPredecessorLink(current, setNumber);
}
AddToSet(newEarleyItem, setNumber + 1, "Scanner");
}
}