anchor.diff:    }
   
     @override
  -  Expression _makeSimpleWrite(Expression value, bool voidContext,
  -      ComplexAssignmentJudgment complexAssignment) {
  -    PropertySet write = new PropertySet(receiver, name, value, setter)
  -      ..fileOffset = fileOffset;
  -    complexAssignment?.write = write;
  -    return write;
  -  }
  -
  -  @override
     Expression _makeRead(ComplexAssignmentJudgment complexAssignment) {
       PropertyGet read = new PropertyGet(receiverAccess(), name, getter)
         ..fileOffset = fileOffset;
  
positive.code:   }
  
    @override
    Expression doInvocation(int offset, Arguments arguments) {
      if (_forest.argumentsPositional(arguments).length > 0 ||
          _forest.argumentsNamed(arguments).length > 0) {
  
negative.code:     VariableDeclaration dummy = new VariableDeclaration.forValue(write);
      return makeLet(
          valueVariable, makeLet(dummy, new VariableGet(valueVariable)));
    }
  
    @override
  