On 03.12.2013 00:01, Krzysztof Czainski wrote:

2013/12/2 Antony Polukhin <antoshkka@gmail.com>

You are absolutely right: ValueType&& any_cast(any&&) was not a good idea and it may break code that accepts result by const reference.

Making it ValueType any_cast(any&&) would be more correct.

I'll fix that as soon as the migration to the GIT will be finished.

Great thanks for finding, investigating and reporting this issue!

Created ticket #9462 : https://svn.boost.org/trac/boost/ticket/9462

Thanks a lot!

That said, what do you gain by doing:

const auto& vec = boost::any_cast<std::vector<int>>(makeVec());

instead of

const auto vec = boost::any_cast<std::vector<int>>(makeVec());

?

Regards,

Kris

In C++11 with a moveable type, probably not much. I don't quite remember why I wrote the code like this - it could have been out of habit since in C++98 using a reference may save a copy, though I guess an optimizing compiler had already been allowed to elide it.

Regards,
Arne