/// <summary>
/// Parses vertex node.
/// </summary>
/// <returns> A vertex node. </returns>
static private Node ParseVertex(ref int position, List <Token> tokens)
{
VertexNode vertexNode = new VertexNode();
CheckLeftParen(ref position, tokens);
// Parse Values of the variable.
Node variableNode = ParseMatchVariable(ref position, tokens);
vertexNode.AddMatchVariable(variableNode);
CheckRightParen(ref position, tokens);
// Position incremented from leaving function PsrseVariable.
// Try parse an Edge.
Node edgeNode = ParseEdge(ref position, tokens);
if (edgeNode != null)
{
vertexNode.AddNext(edgeNode);
return(vertexNode);
}
// Try Parse another pattern, divided by comma.
Node newPattern = ParseNewPatternExpr(ref position, tokens);
if (newPattern != null)
{
vertexNode.AddNext(newPattern);
}
// Always must return valid vertex.
return(vertexNode);
}
/// <summary>
/// Try to jump to a variable node inside the vertex or continue to the edge.
/// </summary>
public void Visit(VertexNode node)
{
this.readingVertex = true;
ParsedPatternNode vm = new VertexParsedPatternNode();
currentPattern.AddParsedPatternNode(vm);
if (node.matchVariable != null)
{
node.matchVariable.Accept(this);
}
if (node.next != null)
{
node.next.Accept(this);
}
}
public void Visit(VertexNode node)
{
throw new NotImplementedException();
}