Sprout/sprout/random/random_result.hpp
2014-08-14 22:55:49 +09:00

407 lines
14 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_RANDOM_RESULT_HPP
#define SPROUT_RANDOM_RANDOM_RESULT_HPP
#include <iterator>
#include <utility>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/workaround/std/cstddef.hpp>
#include <sprout/iterator/next.hpp>
#include <sprout/tuple/tuple.hpp>
#include <sprout/generator/functions.hpp>
#include <sprout/random/random_result_fwd.hpp>
#include <sprout/random/variate_generator.hpp>
#include <sprout/utility/swap.hpp>
#include <sprout/utility/move.hpp>
#include <sprout/type_traits/integral_constant.hpp>
#include <sprout/type_traits/identity.hpp>
#include <sprout/detail/nil_base.hpp>
namespace sprout {
namespace random {
//
// random_result
//
template<typename Engine, typename Distribution>
class random_result<
Engine,
Distribution,
typename std::enable_if<!std::is_same<Distribution, void>::value>::type
>
: public std::iterator<
std::input_iterator_tag,
typename Distribution::result_type,
std::ptrdiff_t,
typename Distribution::result_type const*,
typename Distribution::result_type const&
>
{
public:
typedef Engine engine_type;
typedef Distribution distribution_type;
typedef typename distribution_type::result_type result_type;
typedef sprout::random::variate_generator<engine_type, distribution_type> generator_type;
private:
typedef std::iterator<
std::input_iterator_tag,
result_type,
std::ptrdiff_t,
result_type const*,
result_type const&
> base_type;
public:
typedef typename base_type::iterator_category iterator_category;
typedef typename base_type::value_type value_type;
typedef typename base_type::difference_type difference_type;
typedef typename base_type::pointer pointer;
typedef typename base_type::reference reference;
private:
result_type result_;
generator_type generator_;
public:
SPROUT_CONSTEXPR random_result()
: result_(), generator_()
{}
random_result(random_result const&) = default;
SPROUT_CONSTEXPR random_result(
result_type result,
engine_type const& engine, distribution_type const& distribution
)
: result_(result)
, generator_(engine, distribution)
{}
SPROUT_CONSTEXPR random_result operator()() const {
return generator_();
}
SPROUT_CXX14_CONSTEXPR result_type& generated_value() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type const& generated_value() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CXX14_CONSTEXPR generator_type& next_generator() SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CONSTEXPR generator_type const& next_generator() const SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CXX14_CONSTEXPR result_type& result() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type const& result() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CXX14_CONSTEXPR generator_type& next() SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CONSTEXPR generator_type const& next() const SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CXX14_CONSTEXPR engine_type& engine() SPROUT_NOEXCEPT {
return generator_.engine();
}
SPROUT_CONSTEXPR engine_type const& engine() const SPROUT_NOEXCEPT {
return generator_.engine();
}
SPROUT_CXX14_CONSTEXPR distribution_type& distribution() SPROUT_NOEXCEPT {
return generator_.distribution();
}
SPROUT_CONSTEXPR distribution_type const& distribution() const SPROUT_NOEXCEPT {
return generator_.distribution();
}
SPROUT_CXX14_CONSTEXPR operator result_type&() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR operator result_type const&() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type min() const SPROUT_NOEXCEPT {
return distribution().min();
}
SPROUT_CONSTEXPR result_type max() const SPROUT_NOEXCEPT {
return distribution().max();
}
SPROUT_CXX14_CONSTEXPR void swap(random_result& other)
SPROUT_NOEXCEPT_IF(
SPROUT_NOEXCEPT_EXPR(sprout::swap(result_, other.result_))
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(generator_, other.generator_))
)
{
sprout::swap(result_, other.result_);
sprout::swap(generator_, other.generator_);
}
friend SPROUT_CONSTEXPR bool operator==(random_result const& lhs, random_result const& rhs) SPROUT_NOEXCEPT {
return lhs.result_ == rhs.result_
&& lhs.generator_ == rhs.generator_
;
}
friend SPROUT_CONSTEXPR bool operator!=(random_result const& lhs, random_result const& rhs) SPROUT_NOEXCEPT {
return !(lhs == rhs);
}
SPROUT_CONSTEXPR reference operator*() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR pointer operator->() const SPROUT_NOEXCEPT {
return &result_;
}
SPROUT_CXX14_CONSTEXPR random_result& operator++() {
random_result temp((*this)());
temp.swap(*this);
return *this;
}
SPROUT_CXX14_CONSTEXPR random_result operator++(int) {
random_result result(*this);
++*this;
return result;
}
};
template<typename Engine, typename Distribution>
class random_result<
Engine,
Distribution,
typename std::enable_if<std::is_same<Distribution, void>::value>::type
>
: public std::iterator<
std::input_iterator_tag,
typename Engine::result_type,
std::ptrdiff_t,
typename Engine::result_type const*,
typename Engine::result_type const&
>
{
public:
typedef Engine engine_type;
typedef typename engine_type::result_type result_type;
typedef engine_type generator_type;
private:
typedef std::iterator<
std::input_iterator_tag,
result_type,
std::ptrdiff_t,
result_type const*,
result_type const&
> base_type;
public:
typedef typename base_type::iterator_category iterator_category;
typedef typename base_type::value_type value_type;
typedef typename base_type::difference_type difference_type;
typedef typename base_type::pointer pointer;
typedef typename base_type::reference reference;
private:
result_type result_;
generator_type generator_;
public:
SPROUT_CONSTEXPR random_result()
: result_(), generator_()
{}
random_result(random_result const&) = default;
SPROUT_CONSTEXPR random_result(result_type result, engine_type const& engine)
: result_(result), generator_(engine)
{}
SPROUT_CONSTEXPR random_result operator()() const {
return generator_();
}
SPROUT_CXX14_CONSTEXPR result_type& generated_value() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type const& generated_value() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CXX14_CONSTEXPR generator_type& next_generator() SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CONSTEXPR generator_type const& next_generator() const SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CXX14_CONSTEXPR result_type& result() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type const& result() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CXX14_CONSTEXPR generator_type& next() SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CONSTEXPR generator_type const& next() const SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CXX14_CONSTEXPR engine_type& engine() SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CONSTEXPR engine_type const& engine() const SPROUT_NOEXCEPT {
return generator_;
}
SPROUT_CXX14_CONSTEXPR operator result_type&() SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR operator result_type const&() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR result_type min() const SPROUT_NOEXCEPT {
return engine().min();
}
SPROUT_CONSTEXPR result_type max() const SPROUT_NOEXCEPT {
return engine().max();
}
friend SPROUT_CONSTEXPR bool operator==(random_result const& lhs, random_result const& rhs) SPROUT_NOEXCEPT {
return lhs.result_ == rhs.result_
&& lhs.generator_ == rhs.generator_
;
}
friend SPROUT_CONSTEXPR bool operator!=(random_result const& lhs, random_result const& rhs) SPROUT_NOEXCEPT {
return !(lhs == rhs);
}
SPROUT_CXX14_CONSTEXPR void swap(random_result& other)
SPROUT_NOEXCEPT_IF(
SPROUT_NOEXCEPT_EXPR(sprout::swap(result_, other.result_))
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(generator_, other.generator_))
)
{
sprout::swap(result_, other.result_);
sprout::swap(generator_, other.generator_);
}
SPROUT_CONSTEXPR reference operator*() const SPROUT_NOEXCEPT {
return result_;
}
SPROUT_CONSTEXPR pointer operator->() const SPROUT_NOEXCEPT {
return &result_;
}
SPROUT_CXX14_CONSTEXPR random_result& operator++() {
random_result temp((*this)());
temp.swap(*this);
return *this;
}
SPROUT_CXX14_CONSTEXPR random_result operator++(int) {
random_result result(*this);
random_result temp((*this)());
temp.swap(*this);
return result;
}
};
//
// swap
//
template<typename Engine, typename Distribution>
inline SPROUT_CXX14_CONSTEXPR void
swap(sprout::random::random_result<Engine, Distribution>& lhs, sprout::random::random_result<Engine, Distribution>& rhs)
SPROUT_NOEXCEPT_IF_EXPR(lhs.swap(rhs))
{
lhs.swap(rhs);
}
//
// iterator_next
//
template<typename Engine, typename Distribution>
inline SPROUT_CONSTEXPR sprout::random::random_result<Engine, Distribution>
iterator_next(sprout::random::random_result<Engine, Distribution> const& it) {
return it();
}
} // namespace random
namespace tuples {
namespace detail {
template<std::size_t I, typename T>
struct tuple_element_impl;
template<std::size_t I, typename Engine, typename Distribution>
struct tuple_element_impl<I, sprout::random::random_result<Engine, Distribution> >
: public sprout::detail::nil_base
{};
template<typename Engine, typename Distribution>
struct tuple_element_impl<0, sprout::random::random_result<Engine, Distribution> >
: public sprout::identity<typename sprout::random::random_result<Engine, Distribution>::result_type>
{};
template<typename Engine, typename Distribution>
struct tuple_element_impl<1, sprout::random::random_result<Engine, Distribution> >
: public sprout::identity<typename sprout::random::random_result<Engine, Distribution>::generator_type>
{};
template<std::size_t I, typename T>
struct get_impl;
template<typename Engine, typename Distribution>
struct get_impl<0, sprout::random::random_result<Engine, Distribution> > {
public:
SPROUT_CONSTEXPR typename sprout::random::random_result<Engine, Distribution>::result_type&
operator()(sprout::random::random_result<Engine, Distribution>& t) const {
return t.generated_value();
}
SPROUT_CONSTEXPR typename sprout::random::random_result<Engine, Distribution>::result_type const&
operator()(sprout::random::random_result<Engine, Distribution> const& t) const {
return t.generated_value();
}
};
template<typename Engine, typename Distribution>
struct get_impl<1, sprout::random::random_result<Engine, Distribution> > {
public:
SPROUT_CONSTEXPR typename sprout::random::random_result<Engine, Distribution>::generator_type&
operator()(sprout::random::random_result<Engine, Distribution>& t) const {
return t.next_generator();
}
SPROUT_CONSTEXPR typename sprout::random::random_result<Engine, Distribution>::generator_type const&
operator()(sprout::random::random_result<Engine, Distribution> const& t) const {
return t.next_generator();
}
};
} // namespace detail
} // namespace tuples
} // namespace sprout
namespace std {
#if defined(__clang__)
# pragma clang diagnostic push
# pragma clang diagnostic ignored "-Wmismatched-tags"
#endif
//
// tuple_size
//
template<typename Engine, typename Distribution>
struct tuple_size<sprout::random::random_result<Engine, Distribution> >
: public sprout::integral_constant<std::size_t, 2>
{};
//
// tuple_element
//
template<std::size_t I, typename Engine, typename Distribution>
struct tuple_element<I, sprout::random::random_result<Engine, Distribution> >
: public sprout::tuples::detail::tuple_element_impl<I, sprout::random::random_result<Engine, Distribution> >
{};
#if defined(__clang__)
# pragma clang diagnostic pop
#endif
} // namespace std
namespace sprout {
namespace random {
//
// tuple_get
//
template<std::size_t I, typename Engine, typename Distribution>
inline SPROUT_CONSTEXPR typename sprout::tuples::tuple_element<I, sprout::random::random_result<Engine, Distribution> >::type&
tuple_get(sprout::random::random_result<Engine, Distribution>& t) SPROUT_NOEXCEPT {
static_assert(I < 2, "tuple_get: index out of range");
return sprout::tuples::detail::get_impl<I, sprout::random::random_result<Engine, Distribution> >()(t);
}
template<std::size_t I, typename Engine, typename Distribution>
inline SPROUT_CONSTEXPR typename sprout::tuples::tuple_element<I, sprout::random::random_result<Engine, Distribution> >::type const&
tuple_get(sprout::random::random_result<Engine, Distribution> const& t) SPROUT_NOEXCEPT {
static_assert(I < 2, "tuple_get: index out of range");
return sprout::tuples::detail::get_impl<I, sprout::random::random_result<Engine, Distribution> >()(t);
}
template<std::size_t I, typename Engine, typename Distribution>
inline SPROUT_CONSTEXPR typename sprout::tuples::tuple_element<I, sprout::random::random_result<Engine, Distribution> >::type&&
tuple_get(sprout::random::random_result<Engine, Distribution>&& t) SPROUT_NOEXCEPT {
return sprout::move(sprout::tuples::get<I>(t));
}
} // namespace random
} // namespace sprout
#endif // #ifndef SPROUT_RANDOM_RANDOM_RESULT_HPP