private DFANode DFANodeClone_DFS(Dictionary <DFANode, DFANode> NodeMap, DFANode CurNode)
{
if (NodeMap.ContainsKey(CurNode))
{
return(NodeMap[CurNode]);
}
var newnode = new DFANode {
ID = CurNode.ID, IsEndNode = CurNode.IsEndNode, Edge = new List <DFAEdge>()
};
NodeMap[CurNode] = newnode;
foreach (var item in CurNode.Edge)
{
var newedge = new DFAEdge {
Condition = item.Condition, NextNode = null
};
if (item.NextNode != null)
{
newedge.NextNode = DFANodeClone_DFS(NodeMap, item.NextNode);
}
newnode.Edge.Add(newedge);
}
return(newnode);
}
public Token ReadToken()
{
if (_Index == _Str.Length)
{
return(new Token(TokenState.End, null, null, _Line, _Col));
}
var index = _Index;
var startIndex = index;
var state = _Egt.DFAStateGroup[0];
Symbol acceptSymbol = null;
int accpetIndex = -1;
while (true)
{
DFAEdge edge = null;
if (index <= _Str.Length - 1)
{
var cha = _Str[index];
edge = state.GetEdge(cha);
}
if (edge != null)
{
state = edge.TargetState;
if (state.AcceptSymbol != null)
{
acceptSymbol = state.AcceptSymbol;
accpetIndex = index;
}
index++;
}
else
{
if (acceptSymbol != null)
{
var token = new Token(TokenState.Accept, acceptSymbol,
_Str.Substring(startIndex, accpetIndex - startIndex + 1),
_Line, _Col);
Consumn(token.Value);
return(token);
}
else
{
var token = new Token(TokenState.Error, null, _Str[startIndex].ToString(),
_Line, _Col);
Consumn(token.Value);
return(token);
}
}
}
}
private bool MatchDFA(string Code, int StartIndex, DFANode StartNode, out int Length)
{
var succlength = 0;
var curnode = StartNode;
var curlength = 0;
while (true)
{
if (curnode.IsEndNode)
{
succlength = curlength;
}
if ((StartIndex + curlength) >= Code.Length)
{
break;
}
var matchedge = new DFAEdge();
foreach (var edge in curnode.Edge)
{
if (edge.Condition == Code[StartIndex + curlength])
{
matchedge = edge;
break;
}
}
if (matchedge.NextNode == null)
{
Length = succlength;
break;
}
curnode = matchedge.NextNode;
curlength++;
}
Length = succlength;
return(succlength == 0 ? false : true);
}
