anchor.diff:    /// affect the values of custom properties.
     void updateStyles() => jsElement.callMethod('updateStyles');
   
  -
  -
     /// Sets a value on an attribute path, and notifies of changes.
     void set(String path, value) =>
  -  jsElement.callMethod('set', [path, jsValue(value)]);
  +      jsElement.callMethod('set', [path, jsValue(value)]);
   
     /// Add `item` to a list at `path`.
     void add(String path, item) {
  
positive.code: 
    /// Copies the objects of `iterable`, skipping `skipCount` objects first, into
    /// the range `start`, inclusive, to `end`, exclusive, of the list at `path`.
    void setRange(
        String path, int start, int end, Iterable iterable, [int skipCount = 0]) {
      int numToReplace = end - start;
      jsElement.callMethod(
          'splice',
          [path, start, numToReplace]
            ..addAll(
              iterable
              .skip(skipCount)
              .take(numToReplace)
              .map((element) => jsValue(element))));
    }
  }
  
negative.code: 
    /// Inserts `elements` at position `index` to the list at `path`.
    void insertAll(String path, int index, Iterable elements) {
      jsElement.callMethod('splice',
          [path, index, 0]..addAll(elements.map((element) => jsValue(element))));
    }
  
  