   }
 
   func successor() -> Index {
-    _precondition(nextKeyIndex < allKeys.count, "can not advance endIndex forward")
+    _precondition(
+      nextKeyIndex < allKeys.count, "can not advance endIndex forward")
     return _CocoaDictionaryIndex(cocoaDictionary, allKeys, nextKeyIndex + 1)
   }
 }

  /// This function does *not* update `count`.
  mutating func unsafeAddNew(#key: KeyType, value: ValueType) {
    var (i, found) = _find(key, _bucket(key))
    _sanityCheck(!found, "unsafeAddNew was called, but the key is already present")
    self[i.offset] = Element(key: key, value: value)
  }


  //

  @objc
  init(
    objects: ConstUnsafePointer<AnyObject?>,
    forKeys: ConstUnsafePointer<Void>,
    count: Int
  ) {
    _fatalError("don't call this designated initializer")
  }

