public void e_closure()
{
this.accept = null;
this.anchor = 0;
this.accept_index = 2147483647;
Stack <Nfa> stack = new Stack <Nfa>();
int count = this.nfa_set.Count;
for (int i = 0; i < count; i++)
{
Nfa nfa = this.nfa_set[i];
stack.Push(nfa);
}
while (stack.Count > 0)
{
object obj = stack.Pop();
if (obj == null)
{
break;
}
Nfa nfa = (Nfa)obj;
if (nfa.GetAccept() != null && nfa.Label < this.accept_index)
{
this.accept_index = nfa.Label;
this.accept = nfa.GetAccept();
this.anchor = nfa.GetAnchor();
}
if ('' == nfa.Edge)
{
if (nfa.Next != null && !this.nfa_set.Contains(nfa.Next))
{
this.nfa_bit.Set(nfa.Next.Label, true);
this.nfa_set.Add(nfa.Next);
stack.Push(nfa.Next);
}
if (nfa.Sibling != null && !this.nfa_set.Contains(nfa.Sibling))
{
this.nfa_bit.Set(nfa.Sibling.Label, true);
this.nfa_set.Add(nfa.Sibling);
stack.Push(nfa.Sibling);
}
}
}
if (this.nfa_set != null)
{
this.sort_states();
}
}
/*
* Function: e_closure
* Description: Alters input set.
*/
public void e_closure()
{
Nfa state = null;
/*
* Debug checks
*/
#if DEBUG
Utility.assert(null != nfa_set);
Utility.assert(null != nfa_bit);
#endif
accept = null;
anchor = Spec.NONE;
accept_index = Utility.INT_MAX;
/*
* Create initial stack.
*/
Stack nfa_stack = new Stack();
int size = nfa_set.Count;
for (int i = 0; i < size; i++)
{
state = (Nfa)nfa_set[i];
#if DEBUG
Utility.assert(nfa_bit.Get(state.GetLabel()));
#endif
nfa_stack.Push(state);
}
/*
* Main loop.
*/
while (nfa_stack.Count > 0)
{
Object o = nfa_stack.Pop();
if (o == null)
{
break;
}
state = (Nfa)o;
#if OLD_DUMP_DEBUG
if (null != state.GetAccept())
{
Console.WriteLine("Looking at accepting state "
+ Int32.ToString(state.GetLabel())
+ " with <"
+ state.GetAccept().action
+ ">");
}
#endif
if (null != state.GetAccept() && state.GetLabel() < accept_index)
{
accept_index = state.GetLabel();
accept = state.GetAccept();
anchor = state.GetAnchor();
#if OLD_DUMP_DEBUG
Console.WriteLine("Found accepting state "
+ Int32.ToString(state.GetLabel())
+ " with <"
+ state.GetAccept().action
+ ">");
#endif
#if DEBUG
Utility.assert(null != accept);
Utility.assert(Spec.NONE == anchor ||
0 != (anchor & Spec.END) ||
0 != (anchor & Spec.START));
#endif
}
if (Nfa.EPSILON == state.GetEdge())
{
if (state.GetNext() != null)
{
if (false == nfa_set.Contains(state.GetNext()))
{
#if DEBUG
Utility.assert(false == nfa_bit.Get(state.GetNext().GetLabel()));
#endif
nfa_bit.Set(state.GetNext().GetLabel(), true);
nfa_set.Add(state.GetNext());
nfa_stack.Push(state.GetNext());
}
}
if (null != state.GetSib())
{
if (false == nfa_set.Contains(state.GetSib()))
{
#if DEBUG
Utility.assert(false == nfa_bit.Get(state.GetSib().GetLabel()));
#endif
nfa_bit.Set(state.GetSib().GetLabel(), true);
nfa_set.Add(state.GetSib());
nfa_stack.Push(state.GetSib());
}
}
}
}
if (null != nfa_set)
{
sort_states();
}
}
