Re: [Boost-users] [multi index] combination with boos t::tuple

Markus Werle ha escrito:

Joaquín Mª López Muñoz writes:

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http://lists.boost.org/boost-users/2005/12/16087.php

Thanks for the insight. If only boost::tuples::element::type was a documented feature ...

It's documented, although it's a little hard to find: go to "Advanced features" from Boost.Tuple docs main page.

The inheritance problem you describe is another proof that inheritance should not be used to extend interfaces in generic code and that containment is the superior approach (religious flamewars or very good arguments against this appreciated).

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And the other solution is to write a user-defined extractor as explained in the aforementioned thread.

Your post to comp.std.c++ had no response (thread "Pointer to member contravariance and template non-type arguments") Do you have any new insight on DR or not DR?

No, unfortunately nobody answered. My feeling is that this is a defect, but I don't feel competent enough to file a DR withouht some prior discussion with an expert in the standard. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo