Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

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is_same

template <class T, class U>
struct is_same : public true_type-or-false_type {};

Inherits: If T and U are the same types then inherits from true_type, otherwise inherits from false_type.

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

Compiler Compatibility: If the compiler does not support partial-specialization of class templates, then this template can not be used with abstract, incomplete or function types.

Examples:

is_same<int, int> inherits from true_type.

is_same<int, int>::type is the type true_type.

is_same<int, int>::value is an integral constant expression that evaluates to true.

is_same<int const, int>::value is an integral constant expression that evaluates to false.

is_same<int&, int>::value is an integral constant expression that evaluates to false.

is_same<T, T>::value_type is the type bool.


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