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+/*!
+@file
+Defines `boost::hana::detail::any_of`.
+
+@copyright Louis Dionne 2013-2016
+Distributed under the Boost Software License, Version 1.0.
+(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+ */
+
+#ifndef BOOST_HANA_DETAIL_ANY_OF_HPP
+#define BOOST_HANA_DETAIL_ANY_OF_HPP
+
+#include <boost/hana/config.hpp>
+
+#include <type_traits>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN namespace detail {
+ std::false_type expand(...);
+
+ template <template <typename ...> class Predicate, typename ...T>
+ decltype(expand(
+ typename std::enable_if<!Predicate<T>::value, void*>::type{}...
+ )) any_of_impl(int);
+
+ template <template <typename ...> class Predicate, typename ...T>
+ std::true_type any_of_impl(...);
+
+ //! @ingroup group-details
+ //! Returns whether the `Predicate` is satisfied by any of the `T...`.
+ //!
+ //! This metafunction will short-circuit the evaluation at the first
+ //! type satisfying the predicate, if such a type exists.
+ //!
+ //!
+ //! @note
+ //! The implementation technique used here was originally shown to
+ //! me by Eric Fiselier. All credits where due.
+ template <template <typename ...> class Predicate, typename ...T>
+ struct any_of
+ : decltype(any_of_impl<Predicate, T...>(int{}))
+ { };
+} BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_DETAIL_ANY_OF_HPP