Re: [boost] Proposed SG14 <system_error2> ready for feedback

Subject: Re: [boost] Proposed SG14 <system_error2> ready for feedback
From: Peter Dimov (lists_at_[hidden])
Date: 2018-03-02 20:27:07

Niall Douglas wrote:

> It was fixed by making the category source a constexpr variable, and each 
> is given a 64 bit random unique id by its author from random.org. If the 
> ids match, the domains are considered equal.

That's something I was considering for Boost.System (literally the same 
thing, a random 64 bit ID). Unfortunately, the virtual destructor makes 
error_category a non-literal type, so categories can't be constexpr 
variables. Hence, my earlier inquiry about the switch to a protected 
nonvirtual ~error_category.

There is talk of/hope for language changes allowing constexpr virtuals, but 
it's yet unclear whether we'll get that or if so, when.