public override FST GetFST()
{
FST sub = _Content.GetFST();
// catch a couple of special cases
if (_Lower == 0 && _Upper == 1 || // optional (?)
_Lower == 1 && _Upper == INFINITY || // plus-closure (+)
_Lower == 0 && _Upper == INFINITY) // kleene-closure (*)
{
int subStart = sub.GetStartState();
// the order of the next two tests matters
if (_Upper == INFINITY)
{
List <int> finalStates = sub.GetFinalStates();
/* for each transition ending in a final state, copy that transition to
* point to the single start state
*/
foreach (int source in sub.GetStates())
{
IList <FSTTransition> transitions = sub.GetTransitions(source);
for (int t = transitions.Count - 1; t >= 0; --t)
{
FSTTransition trans = transitions[t];
if (finalStates.Contains(trans.Target))
{
sub.AddTransition(source, subStart, new Label(trans.Input), new Label(trans.Output));
}
}
}
}
if (_Lower == 0)
{
// optionality or kleene star - simply make start state final
sub.SetFinal(subStart, true);
}
}
else
{
throw new NotImplementedException();
}
return(sub);
}
