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Changes needed to make it work when the nested type is void.

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[SVN r16169]
This commit is contained in:
Dave Abrahams
2002-11-09 02:25:38 +00:00
parent 86be3ece35
commit f4f99d8a75
1 changed files with 20 additions and 20 deletions
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40
include/boost/mpl/aux_/has_xxx.hpp
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@@ -30,26 +30,26 @@
// the implementation below is based on a USENET newsgroup's posting by // the implementation below is based on a USENET newsgroup's posting by
// Rani Sharoni (comp.lang.c++.moderated, 2002-03-17 07:45:09 PST) // Rani Sharoni (comp.lang.c++.moderated, 2002-03-17 07:45:09 PST)
# define BOOST_MPL_HAS_XXX_TRAIT_DEF(name) \ # define BOOST_MPL_HAS_XXX_TRAIT_DEF(name) \
template< typename T > \ template< typename T > \
boost::mpl::aux::yes_tag \ boost::mpl::aux::yes_tag \
has_##name##_helper( \ has_##name##_helper( \
boost::mpl::aux::type_wrapper<T>* \ T const volatile* \
, void (*)(BOOST_MSVC_TYPENAME T::name) = 0 \ , boost::mpl::aux::type_wrapper<BOOST_MSVC_TYPENAME T::name>* = 0 \
); \ ); \
\ \
boost::mpl::aux::no_tag has_##name##_helper( \ boost::mpl::aux::no_tag has_##name##_helper( \
... \ ... \
); \ ); \
\ \
template< typename T > \ template< typename T > \
struct has_##name \ struct has_##name \
{ \ { \
BOOST_STATIC_CONSTANT(bool, value = \ BOOST_STATIC_CONSTANT(bool, value = \
sizeof((has_##name##_helper)((boost::mpl::aux::type_wrapper<T>*)0)) \ sizeof((has_##name##_helper)((T*)0)) \
== sizeof(boost::mpl::aux::yes_tag) \ == sizeof(boost::mpl::aux::yes_tag) \
); \ ); \
}; \ }; \
/**/ /**/
# else # else