JOAQUIN LOPEZ MU?Z <joaquin <at> tid.es> writes:
1. What is the compiler error you're getting?
Now, from what you report, seems the restriction is being too much comprehensive. Could you test what is the value of
boost::is_convertible< const name_record::Ptr, const name_record
::value
on your compiler?
No, this thing compiles and expands to false as expected. In fact, the error I'm getting is about boost/boost/type_traits/is_convertible.hpp(254): error: class "name_record" has no suitable copy constructor BOOST_STATIC_CONSTANT(bool, value = ^ detected during: instantiation of class "boost::detail::is_convertible_basic_impl<From, To> [with From=boost::detail::is_convertible_impl<const name_record, const name_record>::ref_type, To=const name_record]" at line 286 instantiation of class "boost::detail::is_convertible_impl<From, To> [with From=const name_record, To=const name_record]" at line 362 instantiation of class "boost::detail::is_convertible_impl_dispatch<From, To> [with From=const name_record, To=const name_record]" at line 409 instantiation of class "boost::is_convertible<From, To> [with From=const name_record, To=const name_record]" at line 59 of "D:\src\3rd- parties\boost/boost/utility/enable_if.hpp" and can be reproduced with bool br = boost::is_convertible< const name_record, const name_record >::value; It fails to compile as well. It seems that is_convertible doesn't handle noncopyable target type well. I believe that this is because they use SFINAE for the check and the try-a-conversion function has the argument by value template <typename From, typename To> struct is_convertible_basic_impl { static ::boost::type_traits::no_type BOOST_TT_DECL _m_check(...); static ::boost::type_traits::yes_type BOOST_TT_DECL _m_check(To); static From _m_from; and compiler fails to pass the argument by value.