bool ok() const;

  // TODO(skyewm): Graph is not part of public API
  Graph* graph() const;

  // TODO(skyewm): Graph is not part of public API
  std::shared_ptr<Graph> graph_as_shared_ptr() const;

  Status status() const;

  /// If status() is ok, convert the Graph object stored in this scope
  /// to a GraphDef proto and return an ok Status. Otherwise, return the error

  }
  return current_constraints;
}

bool Scope::ok() const { return impl()->status_->ok(); }

Graph* Scope::graph() const { return impl()->graph_.get(); }

std::shared_ptr<Graph> Scope::graph_as_shared_ptr() const {
  return impl()->graph_;
}

Status Scope::status() const { return *impl()->status_; }

const std::vector<Operation>& Scope::control_deps() const {
  return impl()->control_deps_;
}