Const and static version for FMT_VARIADIC

[ludekvodicka]

Is there any static and const version for FMT_VARIADIC macro?

Static can be "simulated" by passing static to first param:

FMT_VARIADIC(static void, Write, const char *);

but I didn't find a way how to use FMT_VARIADIC for const method.

Thanks

PS: In all other aspects it's a perfect library. Thanks!

[vitaut]

Is there any static and const version for FMT_VARIADIC macro?

No but it's easy to write them. PRs are welcome =).

If you don't need C++98 support, then I recommend using variadic templates directly instead of FMT_VARIADIC as shown in http://fmtlib.net/latest/api.html#c.FMT_VARIADIC.

[ludekvodicka]

Thanks for the reply.

FMT_VARIADIC is currently better way for me although I don't need C++98. The reason is that I can keep method implementation in cpp file and I don't have to move it to header files as the template.

Regarding PR, I will try to implement it, but I'm not sure if I will be able to.

[vitaut]

FMT_VARIADIC is currently better way for me although I don't need C++98. The reason is that I can keep method implementation in cpp file and I don't have to move it to header files as the template.

You'll be able to do the same in the next version (currently std branch):

// The main formatting function - not a template and can't be defined elsewhere:
std::string vformat(string_view format_str, fmt::args args);

template <typename... Args>
inline std::string format(string_view format_str, const Args & ... args) {
  return vformat(format_str, fmt::make_args(args...));
}

FMT_VARIADIC is for C++-98 compatibility only and will eventually go away.

[ludekvodicka]

I understand that the main reason for FMT_VARIADIC is C++98 compatability.

But I think that this macro also helps with better readability and faster development. It's much easier (and resistant to errors) to write FMT_VARIADIC(...) than writing full variadic template each time.

Because of that, it would be great if you will keep this template also after removing C++98 compatibility. On the other side, it's easy to define such macro in my project in case you will decide to remove it.

[ludekvodicka]

Tried to implement FMT_VARIADIC_CONST as discussed. Hope it's ok (including test in format-test.cc)

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