Boost C++ Libraries

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type_identity

template <class T>
struct type_identity
{
   typedef T type;
};

template <class T> using type_identity_t = typename type_identity<T>::type; // C++11 and above

Header: #include <boost/type_traits/type_identity.hpp> or #include <boost/type_traits.hpp>

Table 1.35. Examples

Expression	Result Type
`type_identity<int>::type`	`int`
`type_identity<int&>::type`	`int&`
`type_identity<int* const&>::type`	`int* const&`