public virtual void AltReferencesTokenID( string ruleName, GrammarAST refAST, int outerAltNum ) { Rule r = GetLocallyDefinedRule( ruleName ); if ( r == null ) { return; } r.TrackTokenReferenceInAlt( refAST, outerAltNum ); if ( !tokenIDRefs.Contains( refAST.Token ) ) { tokenIDRefs.Add( refAST.Token ); } }