What's the canonical way to use the fmtlib with wofstream

Question

We're switching to the fmt library and aim to rewrite many wide character output stream based formattings.

I found fmt::output_file which returns a class ostream : private detail::buffer<char> instance but it looks like there's no support for wchar_t.

What's the canonical way to use the format library in wide character output stream scenarios?

The only way i can think of is to manually open a std::wofstream and use fmt::format. Is this on a roadmap or am i missing something?

Answer 1

fmt/ostream.h provides an fmt::print overload that can write to wofstream:

#include <fmt/ostream.h>
#include <fstream>

int main() {
  std::wofstream ofs("foo");
  fmt::print(ofs, L"The answer is {}.\n", 42);
}

godbolt

That said, I would recommend avoiding wchar_t if you care about portability and performance.