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

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/*!
@file
Forward declares `boost::hana::replace_if`.
@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_REPLACE_IF_HPP
#define BOOST_HANA_FWD_REPLACE_IF_HPP
#include <boost/hana/config.hpp>
#include <boost/hana/core/when.hpp>
BOOST_HANA_NAMESPACE_BEGIN
//! Replace all the elements of a structure satisfying a `predicate`
//! with a fixed value.
//! @ingroup group-Functor
//!
//!
//! Signature
//! ---------
//! Given `F` a Functor and `Bool` a Logical, the signature is
//! \f$
//! \mathtt{replace_if} : F(T) \times (T \to Bool) \times T \to F(T)
//! \f$
//!
//! @param xs
//! The structure to replace elements of.
//!
//! @param predicate
//! A function called as `predicate(x)` for element(s) `x` of the
//! structure and returning a `Logical` representing whether `x`
//! should be replaced by `value`.
//!
//! @param value
//! A value by which every element `x` of the structure for which
//! `predicate` returns a true-valued `Logical` is replaced.
//!
//!
//! Example
//! -------
//! @include example/replace_if.cpp
#ifdef BOOST_HANA_DOXYGEN_INVOKED
constexpr auto replace_if = [](auto&& xs, auto&& predicate, auto&& value) {
return tag-dispatched;
};
#else
template <typename Xs, typename = void>
struct replace_if_impl : replace_if_impl<Xs, when<true>> { };
struct replace_if_t {
template <typename Xs, typename Pred, typename Value>
constexpr auto operator()(Xs&& xs, Pred&& pred, Value&& value) const;
};
constexpr replace_if_t replace_if{};
#endif
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_FWD_REPLACE_IF_HPP