third_party/boost/type_traits/doc/is_detected_exact.qbk

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Copyright 2018 Glen Joseph Fernandes
(glenjofe@gmail.com)

Distributed under the Boost Software License,
Version 1.0. (See accompanying file LICENSE_1_0.txt
or copy at http://www.boost.org/LICENSE_1_0.txt).
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[section:is_detected_exact is_detected_exact]

    template<class Expected, template<class...> class Op, class... Args>
    using is_detected_exact = is_same<Expected, detected_t<Op, Args...> >;

    template<class Expected, template<class...> class Op, class... Args>
    constexpr bool is_detected_exact_v = is_detected_exact<Op, Args...>::value;

__std_paper [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4502.pdf N4502]

__compat Requires C++11 variadic templates and C++11 template aliases.

__header `#include <boost/type_traits/is_detected_exact.hpp>`

The type `is_detected_exact<To, Op, Args>` is an alias for __true_type if the result of 
`Op<Args>` is type `To`.  Otherwise it's the type __false_type;


__examples

    template<class T>
    using difference_t = typename T::difference_type;

    static_assert(boost::is_detected_exact_v<std::ptrdiff_t, difference_t, T>);

See also: __is_detected, __is_detected_convertible.

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