anchor.diff:  
   const $package$operatingSystem = operatingSystem;
   
  +// system
  +
  +class system_ {
  +const system_.$value$();
  +  $dart$core.int get milliseconds
  +      =>  new $dart$core.DateTime.now().millisecondsSinceEpoch;
  +  
  +  $dart$core.int get nanoseconds
  +      =>  new $dart$core.DateTime.now().millisecondsSinceEpoch * 1000000;
  +
  +  $dart$core.String toString()
  +      =>  "Dart";
  +}
  +
  +const system = const system_.$value$();
  +
  +const $package$system = system;
  +
   ////////////////////////////////////////////////////////////////////////////////
   //
   // Runtime Package (ceylon.language.dart)
  
positive.code: 
    Integer get not => new Integer(~_value.toSigned(64));
  
    // Ordinal
  
    Integer get predecessor => new Integer(this._value - 1);
  
negative.code: ///////////////////////////////////////
  
  class Map {}
  class Span {}
  
  ///////////////////////////////////////
  //
  