private static void TrimEndEpsilons(Arc end, Backend backend)
{
Arc endArc = end;
State endState = endArc.Start;
if (endState != null)
{
// Remove the end arc if possible, check done by MoveSemanticTagRight
if (endArc.IsEpsilonTransition && endState.OutArcs.CountIsOne && Graph.MoveSemanticTagLeft(endArc))
{
// State has a single input epsilon transition
// Delete the input epsilon transition and delete state.
endArc.Start = null;
// Remove all the in arcs duplicate the arcs first
foreach (Arc inArc in endState.InArcs.ToList())
{
inArc.End = null;
TrimEndEpsilons(inArc, backend);
}
// Delete the input epsilon transition and delete state if appropriate.
backend.DeleteState(endState);
}
}
}
private static void TrimEndEpsilons(Arc end, Backend backend)
{
State start = end.Start;
if (start != null && end.IsEpsilonTransition && start.OutArcs.CountIsOne && Graph.MoveSemanticTagLeft(end))
{
end.Start = null;
foreach (Arc item in start.InArcs.ToList())
{
item.End = null;
TrimEndEpsilons(item, backend);
}
backend.DeleteState(start);
}
}
