[Boost-bugs] [Boost C++ Libraries] #9840: phoenix V3 and stl container non const methods

Subject: [Boost-bugs] [Boost C++ Libraries] #9840: phoenix V3 and stl container non const methods
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-04-06 08:10:47

#9840: phoenix V3 and stl container non const methods
------------------------------------+---------------------
 Reporter:  Theodore.Papadopoulo@…  |      Owner:  theller
     Type:  Bugs                    |     Status:  new
Milestone:  To Be Determined        |  Component:  phoenix
  Version:  Boost 1.53.0            |   Severity:  Problem
 Keywords:  stl container method    |
------------------------------------+---------------------
 I'm using boost 1.53 (boost-devel-1.53.0-6.fc19.i686).
 I think I found a bug with phoenix and stl methods. It looks like boost
 assumes that all methods are const which is not true (eg vector::reserve).

 I tried to change:

 {{{
 #define BOOST_PHOENIX_ADAPT_CALLABLE(NAME, FUNC, N)
 \
     template <BOOST_PHOENIX_typename_A(N)>
 \
     inline
 \
     typename
 \
         boost::phoenix::detail::expression::function_eval<
 \
             FUNC
 \
           , BOOST_PHOENIX_A(N)>::type const
 \
     NAME(BOOST_PHOENIX_A_const_ref_a(N))
 \
     {
 \
         return boost::phoenix::detail::expression::
 \
             function_eval<FUNC, BOOST_PHOENIX_A(N)>::
 \
                 make(FUNC(), BOOST_PHOENIX_a(N));
 \
     }
 \
 }}}


 into


 {{{
 #define BOOST_PHOENIX_ADAPT_CALLABLE(NAME, FUNC, N)
 \
     template <BOOST_PHOENIX_typename_A(N)>
 \
     inline
 \
     typename
 \
         boost::phoenix::detail::expression::function_eval<
 \
             FUNC
 \
           , BOOST_PHOENIX_A(N)>::type const
 \
     NAME(BOOST_PHOENIX_A_ref_a(N))
 \
     {
 \
         return boost::phoenix::detail::expression::
 \
             function_eval<FUNC, BOOST_PHOENIX_A(N)>::
 \
                 make(FUNC(), BOOST_PHOENIX_a(N));
 \
     }
 \
 }}}


 but that's not enough. That part of the problem remains in git.
 But that is not sufficient, some other method in the chain imposes
 constness.

 phoenix should not try to impose constness IMHO, the chain of
 instantiations should just pass the orginal type...

 Here is a (not totally simplified as it uses spirit) example to reproduce
 the problem:


 {{{
 #include <boost/spirit/include/qi.hpp>
 #include <boost/spirit/include/phoenix.hpp>
 #include <boost/phoenix/stl.hpp>
 #include <boost/spirit/include/qi_uint.hpp>
 #include <boost/phoenix/phoenix.hpp>

 std::vector<unsigned> L;

 int
 main() {
     using namespace boost::spirit::qi;
     using namespace boost::phoenix;
     using boost::phoenix::arg_names::_1;
     const std::string str("3 1 2 3");
     std::string::const_iterator first = str.begin();
     parse(first,str.end(), uint_[reserve(L,_1)] >> repeat(capacity(L))[
 uint_ ]);

 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9840>
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