Method find

extlibs/fmt/include/fmt/core.h:1171–1177

  ~arg_map() { delete[] map_; }

  basic_format_arg<Context> find(basic_string_view<char_type> name) const {
    // The list is unsorted, so just return the first matching name.
    for (entry *it = map_, *end = map_ + size_; it != end; ++it) {
      if (it->name == name) return it->arg;
    }
    return {};
  }
};

// A type-erased reference to an std::locale to avoid heavy <locale> include.