const std::vector<ArgView> &Outputs() const;
  const std::vector<AttrView> &Attributes() const;
  const std::vector<OpArgumentView> &AllArguments() const;

  int NumInputs() const;
  int NumOutputs() const;
  ArgView OnlyInput() const;
  ArgView OnlyOutput() const;

  string FunctionName() const;
  string VariableName() const;
  string OpNameString() const;
  string Summary() const;
  std::vector<string> Description() const;

  return all_arguments_;
}

int OpView::NumInputs() const { return input_args_.size(); }

int OpView::NumOutputs() const { return output_args_.size(); }

ArgView OpView::OnlyInput() const {
  CHECK_EQ(input_args_.size(), 1);  // Crash OK
  return input_args_.front();
}

ArgView OpView::OnlyOutput() const {
  CHECK_EQ(output_args_.size(), 1);  // Crash OK
  return output_args_.front();
}