[Boost-bugs] [Boost C++ Libraries] #12436: Fusion fails if a member type starts with "::"

Subject: [Boost-bugs] [Boost C++ Libraries] #12436: Fusion fails if a member type starts with "::"
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-09-05 03:45:07

#12436: Fusion fails if a member type starts with "::"
------------------------------+---------------------
 Reporter:  jaredgrubb        |      Owner:  djowel
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  fusion
  Version:  Boost 1.59.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+---------------------
 The following code compiles fine in boost-1.57 but fails in boost-1.59 and
 later.

 Example:

 {{{
 #include <string>
 #include <boost/fusion/adapted/struct/define_struct.hpp>
 #include <boost/fusion/include/define_struct.hpp>
 #include <boost/fusion/include/adapt_struct.hpp>

 BOOST_FUSION_DEFINE_STRUCT(
     (demo), employee,
     (::std::size_t, age))
 }}}

 The error shown by clang:

 {{{
 fusion.cpp:6:1: error: pasting formed 'BOOST_PP_IS_EMPTY_DEF_::', an
 invalid preprocessing token
 BOOST_FUSION_DEFINE_STRUCT(
 ^
 /Users/grubber/src/work/boost-1.59.0/boost/fusion/adapted/struct/define_struct.hpp:38:5:
 note: expanded from macro 'BOOST_FUSION_DEFINE_STRUCT'
     BOOST_FUSION_ADAPT_STRUCT(
 \
     ^
 /Users/grubber/src/work/boost-1.59.0/boost/fusion/adapted/struct/adapt_struct.hpp:110:17:
 note: expanded from macro 'BOOST_FUSION_ADAPT_STRUCT'
                 BOOST_FUSION_ADAPT_STRUCT_FILLER_0(0,0)ATTRIBUTES,
 \
                 ^
 /Users/grubber/src/work/boost-1.59.0/boost/fusion/adapted/struct/detail/adapt_base_attr_filler.hpp:25:5:
 note: expanded from macro 'BOOST_FUSION_ADAPT_STRUCT_FILLER_0'
     BOOST_FUSION_ADAPT_STRUCT_FILLER_1
     ^
 note: (skipping 1 expansions in backtrace; use -fmacro-backtrace-limit=0
 to see all)
 /Users/grubber/src/work/boost-1.59.0/boost/fusion/adapted/struct/detail/adapt_base_attr_filler.hpp:35:17:
 note: expanded from macro 'BOOST_FUSION_ADAPT_STRUCT_WRAP_ATTR'
     BOOST_PP_IF(BOOST_PP_IS_EMPTY(X),
 \
                 ^
 /Users/grubber/src/work/boost-1.59.0/boost/preprocessor/facilities/is_empty.hpp:35:34:
 note: expanded from macro 'BOOST_PP_IS_EMPTY'
 #    define BOOST_PP_IS_EMPTY(x) BOOST_PP_IS_EMPTY_I(x
 BOOST_PP_IS_EMPTY_HELPER)
                                  ^
 /Users/grubber/src/work/boost-1.59.0/boost/preprocessor/facilities/is_empty.hpp:36:93:
 note: expanded from macro 'BOOST_PP_IS_EMPTY_I'
 #    define BOOST_PP_IS_EMPTY_I(contents) BOOST_PP_TUPLE_ELEM(2, 1,
 (BOOST_PP_IS_EMPTY_DEF_ ## contents()))
 ^
 1 error generated.
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12436>
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