anchor.diff:    return assetString.substring(0, assetString.length - 1).substring(6);
   }
   
  +String _packagePrefixString =
  +    r'^[^' + (path.separator == '\\' ? r'\\' : '/') + r'|]*\|';
  +RegExp _packagePrefix = new RegExp(_packagePrefixString);
  +
   /// Returns the relative path embedded in the given [fullName], which is
   /// expected to be obtained from `Element.fullName` or some other source
   /// using the same format. This means that the package prefix (for
  
positive.code:             // transformation of libraries in other packages.
              continue;  // Library in different package: cannot be transformed.
            }
            for (Asset input in inputs) {
              if (_isFileAsset(input)) {
                if (_assetPath(input).endsWith(targetPath)) {
                  // NB: This test would yield an incorrect result in the
                  // case where multiple paths in the package have a shared
                  // suffix (e.g., we have both '/path/one/ending/like/this'
  
negative.code: /// such a prefix it is assumed to be a path and returned unchanged.
  String _fullNameToRelativePath(String fullName) {
    if (fullName == null) return null;
    Match match = _packagePrefix.firstMatch(fullName);
    if (match == null) return fullName;
    return path.normalize(fullName.substring(match.end));
  }
  
  /// Returns the package name embedded in the given [fullName], which is
  