Re: [Boost-users] [ptr_map] container equality comparison doesn't compile

Rodolfo Lima skrev:

Hi, is there any other reason (apart from begin a bug) that the following code doesn't compile with g++-4.3?

#include

int main() { boost::ptr_map m1, m2;

m1.insert(1,std::auto_ptr<int>(new int(2))); m2.insert(1,std::auto_ptr<int>(new int(2)));

return m1 == m2; }

gcc spits the following errors (be seated...):

/usr/lib/gcc/i686-pc-linux-gnu/4.3.0/include/g++-v4/bits/stl_algobase.h: In static member function 'static bool std::__equal<_BoolType>::equal(_II1, _II1, _II2) [with _II1 = boost::ptr_map_iterator >, int, const int* const>, _II2 = boost::ptr_map_iterator >, int, const int* const>, bool _BoolType = false]':

/usr/lib/gcc/i686-pc-linux-gnu/4.3.0/include/g++-v4/bits/stl_algobase.h:818: instantiated from 'bool std::__equal_aux(_II1, _II1, _II2) [with _II1 = boost::ptr_map_iterator >, int, const int* const>, _II2 = boost::ptr_map_iterator >, int, const int* const>]'

/usr/lib/gcc/i686-pc-linux-gnu/4.3.0/include/g++-v4/bits/stl_algobase.h:950: instantiated from 'bool std::equal(_II1, _II1, _II2) [with _II1 = boost::ptr_map_iterator >, int, const int* const>, _II2 = boost::ptr_map_iterator >, int, const int* const>]'

/usr/include/boost/ptr_container/detail/reversible_ptr_container.hpp:441: instantiated from 'bool boost::ptr_container_detail::reversible_ptr_container::operator==(const boost::ptr_container_detail::reversible_ptr_container&) const [with Config = boost::ptr_container_detail::map_config > > >, CloneAllocator = boost::heap_clone_allocator]' teste.cpp:10: instantiated from here

/usr/lib/gcc/i686-pc-linux-gnu/4.3.0/include/g++-v4/bits/stl_algobase.h:789: error: no match for 'operator==' in '((boost::iterator_facade >, int, const int* const>, boost::ptr_container_detail::ref_pair, boost::bidirectional_traversal_tag, boost::ptr_container_detail::ref_pair, int>*)(& __first1))->boost::iterator_facade::operator* [with Derived = boost::ptr_map_iterator >, int, const int* const>, Value = boost::ptr_container_detail::ref_pair, CategoryOrTraversal = boost::bidirectional_traversal_tag, Reference = boost::ptr_container_detail::ref_pair, Difference = int]() == ((boost::iterator_facade >, int, const int* const>, boost::ptr_container_detail::ref_pair, boost::bidirectional_traversal_tag, boost::ptr_container_detail::ref_pair, int>*)(& __first2))->boost::iterator_facade::operator* [with Derived = boost::ptr_map_iterator >, int, const int* const>, Value = boost::ptr_container_detail::ref_pair, CategoryOrTraversal = boost::bidirectional_traversal_tag, Reference = boost::ptr_container_detail::ref_pair, Difference = int]()' make: ** [teste] Erro 1

My guess it that boost::ptr_container_detail::ref_pair should have an equality operator (and a less than also) somehow.

In fact... by adding the following operator== to it the code compiles and behaves as expected:

// #include

Something equivalent should be done for operator<

Any objections?

No, I'll add something to trunk soon. Thanks -Thorsten