Re: [boost] variant2 never empty guarantees (was: Re: Outcome/expected/etc/etc/etc)

On Tue, Jun 6, 2017 at 5:29 AM, Andrzej Krzemienski via Boost wrote:

You are basically saying: provide the implementation that gives me strong guarantee when I meet condition X. ("X" being up to one type with potentially throwing move constructor).

Your expectation is reasonable, but (I think) it is incompatible with other peoples' expectation: provide implementation that gives me never-empty guarantee when I meet condition Y. ("Y" in that case means I have a type with nothrow default constructor.)

I do not think both expectations can be satisfied in one implementation.

Regards, &rzej;

Agreed. But I don't see much value in the never-empty guarantee if it doesn't give you the strong guarantee. Tony