How to declare static data members of types?

[jamadagni]

Hello. I know I can declare a static function member of a type just by omitting the this parameter. But how to declare a static data member, such as a list of month names for a Month type, without having it being duplicated for all instances of the type?

Month : type = {
    id_ : int;
    names : std::vector<std::string> = ("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec");
}

[MaxSagebaum]

This is currently not possible.

[zaucy]

If you make names a constexpr it seems to work (tested on latest msvc and latest cppfront)

Month: type = {
	id_: int;
	names: std::vector<std::string> == ("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec");
}

main: () = {
	std::println("hello {}", Month::names.at(0));
}

[jamadagni]

Nice idea, but this will work only for static readonly data like in the above example.

How about static writable data? Those are useful too no?

[hsutter]

Static mutable data is a source of concurrency problems, and I've tried to minimize the ability to write that.

I do allow mutable global variables, but I want to ban them and require using Meyers singletons instead, but I haven't decided on whether I want magic statics to be the syntax for that yet.