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Use boost::hash in hash_value, not std::hash (closes #27)

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This commit is contained in:
Peter Dimov
2021-03-13 05:08:03 +02:00
parent ae1f72671e
commit 3ca95a65df
1 changed files with 11 additions and 4 deletions
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15
include/boost/variant2/variant.hpp
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@ -39,6 +39,8 @@ BOOST_NORETURN void throw_exception( std::exception const & e ); // user defined
#endif
template<class T> struct hash;
namespace variant2
{
@ -2229,7 +2231,7 @@ inline std::size_t hash_value_impl( std::size_t index, std::size_t value )
return hash_value_impl_( mp11::mp_bool< (SIZE_MAX > UINT32_MAX) >(), index, value );
}
template<class V> struct hash_value_L
template<template<class> class H, class V> struct hash_value_L
{
V const & v;
@ -2238,12 +2240,17 @@ template<class V> struct hash_value_L
auto const & t = unsafe_get<I::value>( v );
std::size_t index = I::value;
std::size_t value = std::hash<remove_cv_ref_t<decltype(t)>>()( t );
std::size_t value = H<remove_cv_ref_t<decltype(t)>>()( t );
return hash_value_impl( index, value );
}
};
template<class... T> std::size_t hash_value_std( variant<T...> const & v )
{
return mp11::mp_with_index<sizeof...(T)>( v.index(), detail::hash_value_L< std::hash, variant<T...> >{ v } );
}
} // namespace detail
inline std::size_t hash_value( monostate const & )
@ -2253,7 +2260,7 @@ inline std::size_t hash_value( monostate const & )
template<class... T> std::size_t hash_value( variant<T...> const & v )
{
return mp11::mp_with_index<sizeof...(T)>( v.index(), detail::hash_value_L< variant<T...> >{ v } );
return mp11::mp_with_index<sizeof...(T)>( v.index(), detail::hash_value_L< boost::hash, variant<T...> >{ v } );
}
namespace detail
@ -2274,7 +2281,7 @@ template<class V> struct std_hash_impl<V, true>
{
std::size_t operator()( V const & v ) const
{
return hash_value( v );
return detail::hash_value_std( v );
}
};