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User Defined Specializations

Occationally the end user may need to provide their own specialization for one of the type traits - typically where intrinsic compiler support is required to implement a specific trait fully. These specializations should derive from boost::true_type or boost::false_type as appropriate:

#include <boost/type_traits/is_pod.hpp>
#include <boost/type_traits/is_class.hpp>
#include <boost/type_traits/is_union.hpp>

struct my_pod{};
struct my_union
   char c;
   int i;

namespace boost
   struct is_pod<my_pod> : public true_type{};
   struct is_pod<my_union> : public true_type{};
   struct is_union<my_union> : public true_type{};
   struct is_class<my_union> : public false_type{};
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