Method invoke

paddle/utils/string/tinyformat/tinyformat.h:194–197

template <typename T, bool convertible = is_convertible<T, int>::value>
struct convertToInt {
  static int invoke(const T & /*value*/) {
    throw FormatError();
    return 0;
  }
};
// Specialization for convertToInt when conversion is possible
template <typename T>