anchor.diff:      throw new UnsupportedError(
           "Cannot modify an unmodifiable list");
     }
  -}+}
  
positive.code: 
    @override
    noSuchMethod(Invocation invocation) => reflect(_underlyingUint8List).delegate(invocation);
  }
  
  
  
  
  
  // This code is taken from the dart:_internal library and is licensed
  //  under the same license as all Dart code.
  // Perhaps in the future, this class will be exposed in the dart:collection
  //  library: https://code.google.com/p/dart/issues/detail?id=11178
  /**
   * Mixin for an unmodifiable [List] class.
   *
   * This overrides all mutating methods with methods that throw.
   * This mixin is intended to be mixed in on top of [ListMixin] on
   * unmodifiable lists.
   */
  abstract class _UnmodifiableListMixin<E> implements List<E> {
  
    /** This operation is not supported by an unmodifiable list. */
    void operator []=(int index, E value) {
  
negative.code:  *
   * All methods that can modify the list will throw an [UnsupportedError].
   */
  class UnmodifiableUint8List implements Uint8List {
  
    final Uint8List _underlyingUint8List;
  
  