Syntax question

[hopesfall]

What's going on in the bold part below? I've know that doing something like: PageIterator: page_(NULL) means you're initializing some variable but what does the other part mean?

  PageIterator()
      : page_(NULL) {
    current_record_ = {Page::INVALID_NUMBER, Page::INVALID_SLOT};
  }

[maeriden]

That syntax was added with C++11 to initialize STL containers