anchor.diff:    Iterable follow([$dart$core.Object c])
       =>  new String._fromNative(c.toString() + _value);
   
  -  // bridge methods
  -
  -  @$dart$core.override
  -  $dart$core.bool defines([$dart$core.Object index])
  -    => List.$defines(this, index);
  -
     @$dart$core.override
     $dart$core.bool get empty
       =>  _value == "";
  -
  -  @$dart$core.override
  -  get([$dart$core.Object index])
  -    => List.$get(this, index);
  -
  -  @$dart$core.override
  -  Iterator iterator()
  -    => List.$iterator(this);
  -
  -  @$dart$core.override
  -  getFromLast([index])
  -    => List.$getFromLast(this, index);
  -
  -  @$dart$core.override
  -  $dart$core.int get size
  -    => List.$get$size(this);
  -
  -  @$dart$core.override
  -  $dart$core.Object get first
  -    =>  Iterable.$get$first(this);
  -
  -  @$dart$core.override
  -  Iterable get rest
  -    =>  Iterable.$get$rest(this);
  -
  -  @$dart$core.override
  -  void each([Callable step])
  -    => Iterable.$each(this, step);
  -
  -  @$dart$core.override
  -  Iterable map([Callable collecting])
  -    =>  Iterable.$map(this, collecting);
  -
  -  @$dart$core.override
  -  Iterable flatMap([Callable collecting])
  -    =>  Iterable.$flatMap(this, collecting);
  -
  -  @$dart$core.override
  -  $dart$core.bool contains([$dart$core.Object element])
  -    =>  Collection.$contains(this, element);
  -
  -  @$dart$core.override
  -  Sequential sequence()
  -    =>  Iterable.$sequence(this);
   
     // Dart runtime
   
  
positive.code: // Array.dart
  //
  
  class Array implements List {
    $dart$core.List _list;
  
    Array(Iterable elements) {
  
negative.code: // Tuple.dart
  //
  
  class Tuple extends impl$BaseList implements Sequence, Iterable {
    final $dart$core.List _list;
  
    Tuple($dart$core.Object first, Iterable rest) : _list = [] {
  