anchor.diff:    Map<String, _YamlFileData> get _yamlAtCanonicalPathCache =>
         root.__yamlAtCanonicalPathCache;
   
  -  final ArgParser __argParser = ArgParser(usageLineLength: 80);
  +  final ArgParser __argParser = ArgParser(usageLineLength: _usageLineLength);
   
     ArgParser get argParser => root.__argParser;
   
  
positive.code: library dartdoc.dartdoc_options;
  
  import 'dart:async';
  import 'dart:io' show Platform;
  
  import 'package:analyzer/dart/element/element.dart';
  import 'package:analyzer/file_system/file_system.dart';
  
negative.code: const int _kIntVal = 0;
  const double _kDoubleVal = 0.0;
  const bool _kBoolVal = true;
  
  int get _usageLineLength => stdout.hasTerminal ? stdout.terminalColumns : null;
  
  typedef ConvertYamlToType<T> = T Function(YamlMap, String, ResourceProvider);
  
  