public override DomainId <IAstNode> VisitAddSubtractExpression(QlParser.AddSubtractExpressionContext context) { var leftExpression = Visit(context.leftExpression) .To <ICalculationNode>(m_domainItemLocator); var rightExpression = Visit(context.rightExpression) .To <ICalculationNode>(m_domainItemLocator); var addSubtract = [email protected]; switch (addSubtract) { case QlParser.ADD: return(m_astFactory.CreateAdditionOperation( context.GetText(), leftExpression, rightExpression)); case QlParser.MINUS: return(m_astFactory.CreateSubtractionOperation( context.GetText(), leftExpression, rightExpression)); default: throw new ParserException( $"The provided operator '{[email protected]}' is not handled within add or subtract in the statement {context.GetText()}.", null); } }