anchor.diff:  class Iterable$group$$anonymous$32_ implements Map {
       Iterable $outer$ceylon$language$Iterable;
       Callable $capture$Iterable$group$grouping;
  -    Iterable$group$$anonymous$32_([Iterable this.$outer$ceylon$language$Iterable, Callable this.$capture$Iterable$group$grouping]) {
  +    Iterable$group$$anonymous$32_([Iterable $outer$ceylon$language$Iterable, Callable $capture$Iterable$group$grouping]) {
  +        this.$outer$ceylon$language$Iterable = $outer$ceylon$language$Iterable;
  +        this.$capture$Iterable$group$grouping = $capture$Iterable$group$grouping;
           _$store = (() {
               $dart$core.int arg$133$0 = 16;
               $dart$core.Object arg$133$1 = null;
  
positive.code: class Map$filterKeys$$anonymous$3_ implements Map {
      Map $outer$ceylon$language$Map;
      Callable $capture$Map$filterKeys$filtering;
      Map$filterKeys$$anonymous$3_([Map this.$outer$ceylon$language$Map, Callable this.$capture$Map$filterKeys$filtering]) {}
      $dart$core.Object get([$dart$core.Object key]) => (() {
          $dart$core.bool doElse$19 = true;
          if (key != null) {
  
negative.code: }
  class Map$coalescedMap$$anonymous$5_ implements Map {
      Map $outer$ceylon$language$Map;
      Map$coalescedMap$$anonymous$5_([Map $outer$ceylon$language$Map]) {
          this.$outer$ceylon$language$Map = $outer$ceylon$language$Map;
      }
      $dart$core.bool defines([$dart$core.Object key]) => !($outer$ceylon$language$Map.get(key) == null);
      $dart$core.Object get([$dart$core.Object key]) => $outer$ceylon$language$Map.get(key);
      Iterator iterator() => functionIterable(new dart$Callable(() {
  