Re: [Boost-users] [container / move] return a container of non-copyable but movable from a function in C++03

Ops. I meant I'd like to return a container of non-copyable but movable objects, as shown in the example. WBR, Adam Romanek Dnia 13 sie 2013 o godz. 16:09 Adam Romanek napisał(a):

Hi,

I'd like to return a container of non-movables from a function in C++03 with no success.

here is a sample code that does not compile for me:

#include #include

class non_copyable { BOOST_MOVABLE_BUT_NOT_COPYABLE(non_copyable)

public: non_copyable(){} non_copyable(BOOST_RV_REF(non_copyable)) {} non_copyable& operator=(BOOST_RV_REF(non_copyable)) { return *this; } };

typedef boost::container::vector nc_vector;

nc_vector create() { return nc_vector(); }

int main () { nc_vector v(create()); return 0; }

The compiler says:

(...) /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: error: passing ‘const non_copyable’ as ‘this’ argument of ‘non_copyable::operator boost::rv&()’ discards qualifiers [-fpermissive] (...)

See below for a full compiler output.

I use Boost v1.54 and gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3.

Is it a bug?

Here is the full compiler output:

In file included from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/allocator_traits.hpp:388:0, from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/detail/utilities.hpp:28, from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/vector.hpp:37, from main.cpp:1: /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp: In static member function ‘static void boost::container::allocator_traits<Alloc>::priv_construct_dispatch2(boost::false_type, Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator, boost::false_type = boost::integral_constant]’: /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: instantiated from ‘static void boost::container::allocator_traits<Alloc>::priv_construct(boost::true_type, Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator, boost::true_type = boost::integral_constant]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: instantiated from ‘static void boost::container::allocator_traits<Alloc>::construct(Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/detail/utilities.hpp:555:10: instantiated from ‘typename boost::container::container_detail::disable_if_memcpy_copy_constructible::type boost::container::uninitialized_copy_alloc_n(A&, I, typename std::iterator_traits<_II>::difference_type, F) [with A = std::allocator, I = non_copyable*, F = non_copyable*, typename boost::container::container_detail::disable_if_memcpy_copy_constructible::type = non_copyable*, typename std::iterator_traits<_II>::difference_type = int]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/vector.hpp:734:7: instantiated from ‘boost::container::vector::vector(const boost::container::vector&) [with T = non_copyable, Allocator = std::allocator, boost::container::vector = boost::container::vector]’ main.cpp:16:20: instantiated from here /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: error: passing ‘const non_copyable’ as ‘this’ argument of ‘non_copyable::operator boost::rv&()’ discards qualifiers [-fpermissive]

WBR, Adam Romanek