private void InitializePatternGraph()
{
using (Trace.Entering())
{
// Defines how patterns connect grammar characters.
PatternGraph = new DirectedGraph <GrammarCharacter, Pattern>();
PatternGraph.AddVertices(GrammarCharacterExt.GetValues());
foreach (Pattern pattern in Patterns)
{
// If the pattern connects two grammar characters.
bool isEdge = pattern.LeftRule.GrammarCharacter != GrammarCharacter.e && pattern.RightRule.GrammarCharacter != GrammarCharacter.e;
if (isEdge)
{
PatternGraph.AddEdge(pattern.LeftRule.GrammarCharacter, pattern.RightRule.GrammarCharacter, pattern);
if (pattern.LeftRule.GrammarCharacter != pattern.RightRule.GrammarCharacter)
{
PatternGraph.AddEdge(pattern.RightRule.GrammarCharacter, pattern.LeftRule.GrammarCharacter, pattern);
}
}
}
}
}
