Re: [boost] [optional] How to define boost::none?

2014-11-19 16:58 GMT+01:00 Andrzej Krzemienski :

2014-11-19 16:43 GMT+01:00 Peter Dimov :

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Andrzej Krzemienski wrote:

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2014-11-19 16:28 GMT+01:00 Krzysztof Czainski <1czajnik@gmail.com>:

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And then, why wouldn't a straightforward solution work:

struct none_t {};

none_t const none = {}

I think it validates ODR, or doesn't it?

It does violate ODR at places (without any ill effects AFAIK). Bind's placeholders have the same problem.

Hmm, looks like an option (although technically this is an UB)

But, what would be a practical recommendation for my problem? Is having a "benign" UB like the above an acceptable solution for a Boost library?