anchor.diff:  ///        .single
   ///        .then((row) => print(row.my_field));
   ///
  +@proxy
   abstract class Row {
     operator[] (int i);
     void forEach(void f(String columnName, columnValue));
  
positive.code: import 'package:crypto/crypto.dart';
  import 'dart:io';
  import 'dart:convert';
  
  part 'buffer.dart';
  part 'connection.dart';
  
negative.code: 
  /// Made public for testing.
  String substitute(String source, values) => _substitute(source, values);
  String formatValue(value, String type) => _formatValue(value, type);
  