ecency-mobile/ios/Pods/boost-for-react-native/boost/hana/fwd/not_equal.hpp

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/*!
@file
Forward declares `boost::hana::not_equal`.
@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_FWD_NOT_EQUAL_HPP
#define BOOST_HANA_FWD_NOT_EQUAL_HPP
#include <boost/hana/config.hpp>
#include <boost/hana/core/when.hpp>
#include <boost/hana/detail/nested_to_fwd.hpp>
BOOST_HANA_NAMESPACE_BEGIN
//! Returns a `Logical` representing whether `x` is not equal to `y`.
//! @ingroup group-Comparable
//!
//! The `not_equal` function can be called in two different ways. First,
//! it can be called like a normal function:
//! @code
//! not_equal(x, y)
//! @endcode
//!
//! However, it may also be partially applied to an argument by using
//! `not_equal.to`:
//! @code
//! not_equal.to(x)(y) == not_equal(x, y)
//! @endcode
//!
//! In other words, `not_equal.to(x)` is a function object that is
//! equivalent to `partial(not_equal, x)`. This is provided to enhance
//! the readability of some constructs, especially when using higher
//! order algorithms.
//!
//!
//! Signature
//! ---------
//! Given a Logical `Bool` and two Comparables `A` and `B` that
//! share a common embedding, the signature is
//! @f$ \mathtt{not\_equal} : A \times B \to Bool @f$.
//!
//! @param x, y
//! Two objects to compare for inequality.
//!
//!
//! Example
//! -------
//! @include example/not_equal.cpp
#ifdef BOOST_HANA_DOXYGEN_INVOKED
constexpr auto not_equal = [](auto&& x, auto&& y) {
return tag-dispatched;
};
#else
template <typename T, typename U, typename = void>
struct not_equal_impl : not_equal_impl<T, U, when<true>> { };
struct not_equal_t : detail::nested_to<not_equal_t> {
template <typename X, typename Y>
constexpr auto operator()(X&& x, Y&& y) const;
};
constexpr not_equal_t not_equal{};
#endif
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_FWD_NOT_EQUAL_HPP