public override void Visit(NotExpression e)
 {
     _expression.SetOperand(e);
 }
 public virtual void Visit(NotExpression e)
 {
     _sql.Append(" NOT (");
     e.Operand.Accept(this);
     _sql.Append(")");
 }
 public override void Visit(NotExpression e)
 {
     _expression.Operand = e;
 }
 public virtual void Visit(NotExpression e)
 {
     throw new NotSupportedException();
 }
 public NotExpressionBuilder()
 {
     _expression = new NotExpression();
 }