public override void Visit(FieldExpressionNode node) {
     _writer.WriteLine("Field: ");
     _writer.Indent++;
     _writer.WriteLineIf(node.Field != null, "Name: {0}", node.Field);
     _writer.WriteLineIf(node.Prefix != null, "Prefix: {0}", node.Prefix);
     _writer.Indent--;
 }
        public override void Visit(FieldExpressionNode node) {
            if (String.IsNullOrEmpty(node.Field))
                return;

            _builder.Append(node.Prefix);
            _builder.Append(node.Field);
            _builder.Append(":");
        }
 public virtual void Visit(FieldExpressionNode node) {}