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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
// Rani Sharoni (comp.lang.c++.moderated, 2002-03-17 07:45:09 PST)
# define BOOST_MPL_HAS_XXX_TRAIT_DEF(name) \
template< typename T > \
boost::mpl::aux::yes_tag \
has_##name##_helper( \
boost::mpl::aux::type_wrapper<T>* \
, void (*)(BOOST_MSVC_TYPENAME T::name) = 0 \
); \
\
boost::mpl::aux::no_tag has_##name##_helper( \
... \
); \
\
template< typename T > \
struct has_##name \
{ \
BOOST_STATIC_CONSTANT(bool, value = \
sizeof((has_##name##_helper)((boost::mpl::aux::type_wrapper<T>*)0)) \
== sizeof(boost::mpl::aux::yes_tag) \
); \
}; \
# define BOOST_MPL_HAS_XXX_TRAIT_DEF(name) \
template< typename T > \
boost::mpl::aux::yes_tag \
has_##name##_helper( \
T const volatile* \
, boost::mpl::aux::type_wrapper<BOOST_MSVC_TYPENAME T::name>* = 0 \
); \
\
boost::mpl::aux::no_tag has_##name##_helper( \
... \
); \
\
template< typename T > \
struct has_##name \
{ \
BOOST_STATIC_CONSTANT(bool, value = \
sizeof((has_##name##_helper)((T*)0)) \
== sizeof(boost::mpl::aux::yes_tag) \
); \
}; \
/**/
# else