private PdlTerm VisitTermNode(IInternalTreeNode node)
{
PdlFactor factor = null;
PdlTerm term = null;
for (int c = 0; c < node.Children.Count; c++)
{
var child = node.Children[c];
switch (child.NodeType)
{
case TreeNodeType.Internal:
var internalNode = child as IInternalTreeNode;
var symbolValue = internalNode.Symbol.Value;
if (PdlGrammar.Factor == symbolValue)
{
factor = VisitFactorNode(internalNode);
}
else if (PdlGrammar.Term == symbolValue)
{
term = VisitTermNode(internalNode);
}
break;
case TreeNodeType.Token:
break;
}
}
if (term is null)
{
return(new PdlTerm(factor));
}
return(new PdlTermConcatenation(factor, term));
}
private PdlExpression VisitExpressionNode(IInternalTreeNode node)
{
PdlTerm term = null;
PdlExpression expression = null;
for (int c = 0; c < node.Children.Count; c++)
{
var child = node.Children[c];
switch (child.NodeType)
{
case TreeNodeType.Internal:
var internalNode = child as IInternalTreeNode;
var symbolValue = internalNode.Symbol.Value;
if (PdlGrammar.Term == symbolValue)
{
term = VisitTermNode(internalNode);
}
else if (PdlGrammar.Expression == symbolValue)
{
expression = VisitExpressionNode(internalNode);
}
break;
case TreeNodeType.Token:
break;
}
}
if (expression is null)
{
return(new PdlExpression(term));
}
return(new PdlExpressionAlteration(term, expression));
}
public PdlExpressionAlteration(
PdlTerm term,
PdlExpression expression)
: base(term)
{
Expression = expression;
_hashCode = ComputeHashCode();
}
IEnumerable <ProductionModel> Term(PdlTerm term, ProductionModel currentProduction)
{
foreach (var production in Factor(term.Factor, currentProduction))
{
yield return(production);
}
if (term.NodeType != PdlNodeType.PdlTermConcatenation)
{
yield break;
}
var concatenation = term as PdlTermConcatenation;
foreach (var production in Term(concatenation.Term, currentProduction))
{
yield return(production);
}
}
public PdlTermConcatenation(PdlFactor factor, PdlTerm term)
: base(factor)
{
Term = term;
_hashCode = ComputeHashCode();
}
public PdlExpression(PdlTerm term)
{
Term = term;
_hashCode = ComputeHashCode();
}