Sprout/sprout/random/generate_array.hpp

62 lines
2.3 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
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 SPROUT_RANDOM_GENERATE_ARRAY_HPP
#define SPROUT_RANDOM_GENERATE_ARRAY_HPP
#include <cstddef>
#include <sprout/config.hpp>
#include <sprout/array/array.hpp>
#include <sprout/utility/pair/pair.hpp>
namespace sprout {
namespace random {
//
// generate_array
//
template<std::size_t N, typename URNG>
inline SPROUT_CXX14_CONSTEXPR sprout::array<typename URNG::result_type, N>
generate_array(URNG& rng) {
sprout::array<typename URNG::result_type, N> result{{}};
for (std::size_t i = 0; i != N; ++i) {
result[i] = rng();
}
return result;
}
namespace detail {
template<std::size_t N, typename URNG, typename Random, typename... Args>
static SPROUT_CONSTEXPR typename std::enable_if<
(sizeof...(Args) + 1 == N),
sprout::pair<sprout::array<typename URNG::result_type, N>, URNG> const
>::type generate_array_impl(Random const& rnd, Args const&... args) {
typedef sprout::pair<sprout::array<typename URNG::result_type, N>, URNG> const pair_type;
return pair_type{
sprout::array<typename URNG::result_type, N>{{args..., rnd.result()}},
rnd.engine()
};
}
template<std::size_t N, typename URNG, typename Random, typename... Args>
static SPROUT_CONSTEXPR typename std::enable_if<
(sizeof...(Args) + 1 < N),
sprout::pair<sprout::array<typename URNG::result_type, N>, URNG> const
>::type generate_array_impl(Random const& rnd, Args const&... args) {
return sprout::random::detail::generate_array_impl<N, URNG>(rnd(), args..., rnd.result());
}
} // namespace detail
//
// generate_array
//
template<std::size_t N, typename URNG>
inline SPROUT_CONSTEXPR sprout::pair<sprout::array<typename URNG::result_type, N>, URNG> const
generate_array(URNG const& rng) {
return sprout::random::detail::generate_array_impl<N, URNG>(rng());
}
} // namespace random
} // namespace sprout
#endif // #ifndef SPROUT_RANDOM_GENERATE_ARRAY_HPP