gnss-sim/3rdparty/boost/cobalt/race.hpp

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//
// Copyright (c) 2022 Klemens Morgenstern (klemens.morgenstern@gmx.net)
//
// 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)
//
#ifndef BOOST_COBALT_RACE_HPP
#define BOOST_COBALT_RACE_HPP
#include <boost/cobalt/concepts.hpp>
#include <boost/cobalt/detail/race.hpp>
#include <boost/cobalt/detail/wrapper.hpp>
#include <random>
namespace boost::cobalt
{
namespace detail
{
inline std::default_random_engine &prng()
{
thread_local static std::default_random_engine g(std::random_device{}());
return g;
}
}
// tag::concept[]
template<typename G>
concept uniform_random_bit_generator =
requires ( G & g)
{
{typename std::decay_t<G>::result_type() } -> std::unsigned_integral; // is an unsigned integer type
// T Returns the smallest value that G's operator() may return. The value is strictly less than G::max(). The function must be constexpr.
{std::decay_t<G>::min()} -> std::same_as<typename std::decay_t<G>::result_type>;
// T Returns the largest value that G's operator() may return. The value is strictly greater than G::min(). The function must be constexpr.
{std::decay_t<G>::max()} -> std::same_as<typename std::decay_t<G>::result_type>;
{g()} -> std::same_as<typename std::decay_t<G>::result_type>;
} && (std::decay_t<G>::max() > std::decay_t<G>::min());
// end::concept[]
template<asio::cancellation_type Ct = asio::cancellation_type::all,
uniform_random_bit_generator URBG,
awaitable<detail::fork::promise_type> ... Promise>
auto race(URBG && g, Promise && ... p) -> detail::race_variadic_impl<Ct, URBG, Promise ...>
{
return detail::race_variadic_impl<Ct, URBG, Promise ...>(std::forward<URBG>(g), static_cast<Promise&&>(p)...);
}
template<asio::cancellation_type Ct = asio::cancellation_type::all,
uniform_random_bit_generator URBG,
typename PromiseRange>
requires awaitable<std::decay_t<decltype(*std::declval<PromiseRange>().begin())>,
detail::fork::promise_type>
auto race(URBG && g, PromiseRange && p) -> detail::race_ranged_impl<Ct, URBG, PromiseRange>
{
if (std::empty(p))
throw_exception(std::invalid_argument("empty range raceed"));
return detail::race_ranged_impl<Ct, URBG, PromiseRange>{std::forward<URBG>(g), static_cast<PromiseRange&&>(p)};
}
template<asio::cancellation_type Ct = asio::cancellation_type::all,
awaitable<detail::fork::promise_type> ... Promise>
auto race(Promise && ... p) -> detail::race_variadic_impl<Ct, std::default_random_engine&, Promise ...>
{
return race<Ct>(detail::prng(), static_cast<Promise&&>(p)...);
}
template<asio::cancellation_type Ct = asio::cancellation_type::all, typename PromiseRange>
requires awaitable<std::decay_t<decltype(*std::declval<PromiseRange>().begin())>,
detail::fork::promise_type>
auto race(PromiseRange && p) -> detail::race_ranged_impl<Ct, std::default_random_engine&, PromiseRange>
{
if (std::empty(p))
throw_exception(std::invalid_argument("empty range raceed"));
return race<Ct>(detail::prng(), static_cast<PromiseRange&&>(p));
}
template<asio::cancellation_type Ct = asio::cancellation_type::all,
awaitable<detail::fork::promise_type> ... Promise>
auto left_race(Promise && ... p) -> detail::race_variadic_impl<Ct, detail::left_race_tag, Promise ...>
{
return detail::race_variadic_impl<Ct, detail::left_race_tag, Promise ...>(
detail::left_race_tag{}, static_cast<Promise&&>(p)...);
}
template<asio::cancellation_type Ct = asio::cancellation_type::all, typename PromiseRange>
requires awaitable<std::decay_t<decltype(*std::declval<PromiseRange>().begin())>,
detail::fork::promise_type>
auto left_race(PromiseRange && p) -> detail::race_ranged_impl<Ct, detail::left_race_tag, PromiseRange>
{
if (std::empty(p))
throw_exception(std::invalid_argument("empty range left_raceed"));
return detail::race_ranged_impl<Ct, detail::left_race_tag, PromiseRange>{
detail::left_race_tag{}, static_cast<PromiseRange&&>(p)};
}
}
#endif //BOOST_COBALT_RACE_HPP