anchor.diff:      $dart$core.bool get letter => lowercase || uppercase;
       $dart$core.bool get whitespace => $package$wsChars.contains(new Integer(integer));
       $dart$core.bool get control => Boolean.nativeValue($package$nothing as Boolean);
  -    Comparison compare([Char other]) => (new Integer(integer)).compare(new Integer(other.integer));
  +    Comparison compare([BaseCharacter other]) => (new Integer(integer)).compare(new Integer(other.integer));
       $dart$core.bool operator ==($dart$core.Object that) => (() {
           $dart$core.bool doElse$2 = true;
  -        if (that is Char) {
  -            Char that$3;
  -            that$3 = that as Char;
  +        if (that is Character) {
  +            Character that$3;
  +            that$3 = that as Character;
               doElse$2 = false;
               return integer == that$3.integer;
           }
  
positive.code:         }
      })();
      $dart$core.int get hashCode => integer;
      Char get predecessor => new Char(integer - 1);
      Char get successor => new Char(integer + 1);
      Char neighbour([$dart$core.int offset]) => new Char(integer + offset);
      $dart$core.int offset([Char other]) => integer - other.integer;
      $dart$core.int offsetSign([Char other]) => (new Integer(offset(other))).sign;
      $dart$core.bool operator >(Char other) => integer > other.integer;
      $dart$core.bool operator <(Char other) => integer < other.integer;
      $dart$core.bool operator >=(Char other) => integer >= other.integer;
      $dart$core.bool operator <=(Char other) => integer <= other.integer;
  }
  $dart$core.String $package$className([$dart$core.Object obj]) => $ceylon$interop$dart.runtimeType(obj).toString();
  
  
negative.code:     }
      $dart$core.int integer;
      $dart$core.String toString() => (new $dart$core.String.fromCharCode(integer)).toString();
      Character get lowercased => $package$characterFromInteger(($ceylon$interop$dart.dartString(String.instance(toString()).lowercased).runes.elementAt(0) as $dart$core.num).toInt());
      Character get uppercased => $package$characterFromInteger(($ceylon$interop$dart.dartString(String.instance(toString()).uppercased).runes.elementAt(0) as $dart$core.num).toInt());
      Character get titlecased => uppercased;
      $dart$core.bool get lowercase => !(uppercased == this);
      $dart$core.bool get uppercase => !(lowercased == this);
      $dart$core.bool get titlecase => uppercase;
  