private void ComputeIncludes()
{
// (p,A) include (q,B) iff B -> Beta A Gamma and Gamma => empty and q -> Beta -> p
foreach (AutomatonState q in states)
{
foreach (Transition qB in q.nonTerminalTransitions.Values)
{
foreach (Production prod in qB.A.productions)
{
for (int i = prod.rhs.Count - 1; i >= 0; i--)
{
Symbol A = prod.rhs[i];
NonTerminal NT = A as NonTerminal;
if (NT != null)
{
AutomatonState p = PathTo(q, prod, i);
p.nonTerminalTransitions[NT].includes.Add(qB);
}
if (!A.IsNullable())
{
break;
}
}
}
}
}
}
internal static void PopulatePrefixes(List <AutomatonState> states)
{
AutomatonState start = states[0];
start.shortestPrefix = new List <Symbol>(); // The empty list.
start.statePath = new List <AutomatonState>();
start.statePath.Add(start);
bool changed = false;
do
{
changed = false;
foreach (AutomatonState state in states)
{
List <Symbol> newfix;
List <Symbol> prefix = state.shortestPrefix;
List <AutomatonState> newPath;
List <AutomatonState> oldPath = state.statePath;
if (prefix != null)
{
foreach (KeyValuePair <Symbol, AutomatonState> a in state.Goto)
{
Symbol smbl = a.Key;
AutomatonState nextState = a.Value;
newfix = ListClone <Symbol>(prefix);
newPath = ListClone <AutomatonState>(oldPath);
newPath.Add(nextState);
if (!smbl.IsNullable())
{
newfix.Add(smbl);
}
if (nextState.shortestPrefix == null ||
nextState.shortestPrefix.Count > newfix.Count)
{
nextState.shortestPrefix = newfix;
nextState.statePath = newPath;
changed = true;
}
}
}
}
} while (changed);
}
