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/*!
@file
Forward declares `boost::hana::repeat`.
@copyright Louis Dionne 2013-2017
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_REPEAT_HPP
#define BOOST_HANA_FWD_REPEAT_HPP
#include <boost/hana/config.hpp>
#include <boost/hana/core/when.hpp>
BOOST_HANA_NAMESPACE_BEGIN
//! Invokes a nullary function `n` times.
//! @ingroup group-IntegralConstant
//!
//! Given an `IntegralConstant` `n` and a nullary function `f`,
//! `repeat(n, f)` will call `f` `n` times. In particular, any
//! decent compiler should expand `repeat(n, f)` to
//! @code
//! f(); f(); ... f(); // n times total
//! @endcode
//!
//!
//! @param n
//! An `IntegralConstant` holding a non-negative value representing
//! the number of times `f` should be repeatedly invoked.
//!
//! @param f
//! A function to repeatedly invoke `n` times. `f` is allowed to have
//! side effects.
//!
//!
//! Example
//! -------
//! @include example/repeat.cpp
#ifdef BOOST_HANA_DOXYGEN_INVOKED
constexpr auto repeat = [](auto const& n, auto&& f) -> void {
f(); f(); ... f(); // n times total
};
#else
template <typename N, typename = void>
struct repeat_impl : repeat_impl<N, when<true>> { };
struct repeat_t {
template <typename N, typename F>
constexpr void operator()(N const& n, F&& f) const;
};
constexpr repeat_t repeat{};
#endif
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_FWD_REPEAT_HPP
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