Re: [Boost-users] Pointer Container Library changes in 1.66.0

On Thu, Apr 5, 2018 at 12:35 PM, Daniel James via Boost-users < boost-users@lists.boost.org> wrote:

On 5 April 2018 at 17:45, Nevin Liber wrote:

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On Thu, Apr 5, 2018 at 11:25 AM, Daniel James via Boost-users wrote:

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On 5 April 2018 at 16:11, Thorsten Ottosen via Boost-users wrote:

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It's the fact that one of the merged changes was to inherit privately from the clone_allocator which in turn forbids the use of final classes as clone_allocator types.

Oh, that's something I haven't thought about. There are quite a few places in boost where inheritance from generic types is used, presumably they've all got the same problem. I'm not sure if there's a good way to handle this.

Can't you just wrap it and derive from the wrapper?

For instance, I have a wrapper (which is a little overkill for this) at ebo_wrapper.h. My version uses the traits in std, but Boost.TypeTraits has equivalents.

boost::is_final doesn't work everywhere, and std::is_final is C++14, so I don't think we've got wide enough support.

Can't we assume either (a) users specialize it (as the documentation says to) or (b) more pessimistically assume all classes are final for C++11 or later compilers when BOOST_IS_FINAL is not defined? -- Nevin ":-)" Liber mailto:nevin@eviloverlord.com +1-847-691-1404