private void Scan(INormalState scan, int j, IToken token)
{
var i = scan.Origin;
var currentSymbol = scan.PostDotSymbol;
var lexerRule = currentSymbol as ILexerRule;
if (token.TokenType == lexerRule.TokenType)
{
var tokenNode = _nodeSet.AddOrGetExistingTokenNode(token);
var nextState = scan.NextState();
var parseNode = CreateParseNode(
nextState,
scan.ParseNode,
tokenNode,
j + 1);
nextState.ParseNode = parseNode;
if (_chart.Enqueue(j + 1, nextState))
LogScan(j + 1, nextState, token);
}
}
private void PredictProduction(INormalState evidence, int j, IProduction production)
{
// TODO: Pre-Compute Leo Items. If item is 1 step from being complete, add a transition item
var predictedState = new NormalState(production, 0, j);
if (_chart.Enqueue(j, predictedState))
Log("Predict", j, predictedState);
var isNullable = Grammar.IsNullable(evidence.PostDotSymbol as INonTerminal);
if (isNullable)
{
var nullParseNode = CreateNullParseNode(evidence.PostDotSymbol, j);
var aycockHorspoolState = evidence.NextState();
var evidenceParseNode = evidence.ParseNode as IInternalForestNode;
if (evidenceParseNode == null)
aycockHorspoolState.ParseNode = CreateParseNode(aycockHorspoolState, null, nullParseNode, j);
else if (evidenceParseNode.Children.Count > 0
&& evidenceParseNode.Children[0].Children.Count > 0)
{
var firstChildNode = evidenceParseNode;
var parseNode = CreateParseNode(aycockHorspoolState, firstChildNode, nullParseNode, j);
aycockHorspoolState.ParseNode = parseNode;
}
if (_chart.Enqueue(j, aycockHorspoolState))
Log("Predict", j, aycockHorspoolState);
}
}