[Boost-bugs] [Boost C++ Libraries] #5626: Compilation error when using boost::phoenix with range adaptors

Subject: [Boost-bugs] [Boost C++ Libraries] #5626: Compilation error when using boost::phoenix with range adaptors
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-06-21 15:33:36

#5626: Compilation error when using boost::phoenix with range adaptors
------------------------------------------------------+---------------------
 Reporter:  Nicolas Savoire <nicos@…>                 |       Owner:  theller   
     Type:  Bugs                                      |      Status:  new       
Milestone:  To Be Determined                          |   Component:  phoenix   
  Version:  Boost Release Branch                      |    Severity:  Regression
 Keywords:                                            |  
------------------------------------------------------+---------------------
 The following piece of code fails to compile with gcc-4.5:
 {{{
 #include <iostream>
 #include <boost/range.hpp>
 #include <boost/range/irange.hpp>
 #include <boost/range/adaptors.hpp>
 #include <boost/phoenix.hpp>

 using namespace boost::phoenix::arg_names;
 using namespace boost::adaptors;

 int main()
 {
   std::cout << *boost::begin(boost::irange(0,5) | transformed( arg1 +1));
 }

 }}}

 The error is:
 {{{
 In file included from /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/range/adaptor/transformed.hpp:16:0,
                  from /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/range/adaptor/map.hpp:14,
                  from /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/range/adaptors.hpp:20,
                  from test2.cpp:4:
 /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/iterator/transform_iterator.hpp: In member
 function ‘typename boost::detail::transform_iterator_base<UnaryFunc,
 Iterator, Reference, Value>::type::reference
 boost::transform_iterator<UnaryFunction, Iterator, Reference,
 Value>::dereference() const [with UnaryFunc =
 boost::phoenix::actor<boost::proto::exprns_::basic_expr<boost::proto::tag::terminal,
 boost::proto::argsns_::term<boost::phoenix::argument<1> >, 0l> >, Iterator
 = boost::range_detail::integer_iterator<int>, Reference =
 boost::use_default, Value = boost::use_default, typename
 boost::detail::transform_iterator_base<UnaryFunc, Iterator, Reference,
 Value>::type::reference = int&]’:
 /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/iterator/iterator_facade.hpp:517:32:
 instantiated from ‘static typename Facade::reference
 boost::iterator_core_access::dereference(const Facade&) [with Facade =
 boost::transform_iterator<boost::phoenix::actor<boost::proto::exprns_::basic_expr<boost::proto::tag::terminal,
 boost::proto::argsns_::term<boost::phoenix::argument<1> >, 0l> >,
 boost::range_detail::integer_iterator<int>, boost::use_default,
 boost::use_default>, typename Facade::reference = int&]’
 /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/iterator/iterator_facade.hpp:643:67:
 instantiated from ‘reference boost::iterator_facade<I, V, TC, R,
 D>::operator*() const [with Derived =
 boost::transform_iterator<boost::phoenix::actor<boost::proto::exprns_::basic_expr<boost::proto::tag::terminal,
 boost::proto::argsns_::term<boost::phoenix::argument<1> >, 0l> >,
 boost::range_detail::integer_iterator<int>, boost::use_default,
 boost::use_default>, Value = int, CategoryOrTraversal =
 boost::detail::iterator_category_with_traversal<std::input_iterator_tag,
 boost::random_access_traversal_tag>, Reference = int&, Difference = long
 int, reference = int&]’
 test2.cpp:13:70:   instantiated from here
 /usr/local/mkt-
 dev/src/boost_1_47_0_rc/boost/iterator/transform_iterator.hpp:121:31:
 error: invalid initialization of reference of type ‘int&’ from expression
 of type ‘const int’
 }}}

 It seems that result_of<arg1(int)> returns int& instead of int.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5626>
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