Method write_float

source/extern/fmt/format.h:2721–2732

template <typename OutputIt, typename DecimalFP, typename Char>
FMT_CONSTEXPR20 auto write_float(OutputIt out, const DecimalFP& f,
                                 const format_specs<Char>& specs,
                                 float_specs fspecs, locale_ref loc)
    -> OutputIt {
  if (is_constant_evaluated()) {
    return do_write_float<OutputIt, DecimalFP, Char,
                          fallback_digit_grouping<Char>>(out, f, specs, fspecs,
                                                         loc);
  } else {
    return do_write_float(out, f, specs, fspecs, loc);
  }
}

template <typename T> constexpr auto isnan(T value) -> bool {
  return !(value >= value);  // std::isnan doesn't support __float128.