// MPark.Variant
//
// Copyright Michael Park, 2015-2017
//
// 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 MPARK_LIB_HPP
#define MPARK_LIB_HPP
#include <memory>
#include <functional>
#include <type_traits>
#include <utility>
#include "config.hpp"
#define RETURN(...) \
noexcept(noexcept(__VA_ARGS__)) -> decltype(__VA_ARGS__) { \
return __VA_ARGS__; \
}
namespace mpark {
namespace lib {
template <typename T>
struct identity { using type = T; };
inline namespace cpp14 {
template <typename T, std::size_t N>
struct array {
constexpr const T &operator[](std::size_t index) const {
return data[index];
}
T data[N == 0 ? 1 : N];
};
template <typename T>
using add_pointer_t = typename std::add_pointer<T>::type;
template <typename... Ts>
using common_type_t = typename std::common_type<Ts...>::type;
template <typename T>
using decay_t = typename std::decay<T>::type;
template <bool B, typename T = void>
using enable_if_t = typename std::enable_if<B, T>::type;
template <typename T>
using remove_const_t = typename std::remove_const<T>::type;
template <typename T>
using remove_reference_t = typename std::remove_reference<T>::type;
template <typename T>
inline constexpr T &&forward(remove_reference_t<T> &t) noexcept {
return static_cast<T &&>(t);
}
template <typename T>
inline constexpr T &&forward(remove_reference_t<T> &&t) noexcept {
static_assert(!std::is_lvalue_reference<T>::value,
"can not forward an rvalue as an lvalue");
return static_cast<T &&>(t);
}
template <typename T>
inline constexpr remove_reference_t<T> &&move(T &&t) noexcept {
return static_cast<remove_reference_t<T> &&>(t);
}
#ifdef MPARK_INTEGER_SEQUENCE
template <typename T, T... Is>
using integer_sequence = std::integer_sequence<T, Is...>;
template <std::size_t... Is>
using index_sequence = std::index_sequence<Is...>;
template <std::size_t N>
using make_index_sequence = std::make_index_sequence<N>;
template <typename... Ts>
using index_sequence_for = std::index_sequence_for<Ts...>;
#else
template <typename T, T... Is>
struct integer_sequence {
using value_type = T;
static constexpr std::size_t size() noexcept { return sizeof...(Is); }
};
template <std::size_t... Is>
using index_sequence = integer_sequence<std::size_t, Is...>;
template <typename Lhs, typename Rhs>
struct make_index_sequence_concat;
template <std::size_t... Lhs, std::size_t... Rhs>
struct make_index_sequence_concat<index_sequence<Lhs...>,
index_sequence<Rhs...>>
: identity<index_sequence<Lhs..., (sizeof...(Lhs) + Rhs)...>> {};
template <std::size_t N>
struct make_index_sequence_impl;
template <std::size_t N>
using make_index_sequence = typename make_index_sequence_impl<N>::type;
template <std::size_t N>
struct make_index_sequence_impl
: make_index_sequence_concat<make_index_sequence<N / 2>,
make_index_sequence<N - (N / 2)>> {};
template <>
struct make_index_sequence_impl<0> : identity<index_sequence<>> {};
template <>
struct make_index_sequence_impl<1> : identity<index_sequence<0>> {};
template <typename... Ts>
using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
#endif
// <functional>
#ifdef MPARK_TRANSPARENT_OPERATORS
using equal_to = std::equal_to<>;
#else
struct equal_to {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) == lib::forward<Rhs>(rhs))
};
#endif
#ifdef MPARK_TRANSPARENT_OPERATORS
using not_equal_to = std::not_equal_to<>;
#else
struct not_equal_to {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) != lib::forward<Rhs>(rhs))
};
#endif
#ifdef MPARK_TRANSPARENT_OPERATORS
using less = std::less<>;
#else
struct less {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) < lib::forward<Rhs>(rhs))
};
#endif
#ifdef MPARK_TRANSPARENT_OPERATORS
using greater = std::greater<>;
#else
struct greater {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) > lib::forward<Rhs>(rhs))
};
#endif
#ifdef MPARK_TRANSPARENT_OPERATORS
using less_equal = std::less_equal<>;
#else
struct less_equal {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) <= lib::forward<Rhs>(rhs))
};
#endif
#ifdef MPARK_TRANSPARENT_OPERATORS
using greater_equal = std::greater_equal<>;
#else
struct greater_equal {
template <typename Lhs, typename Rhs>
inline constexpr auto operator()(Lhs &&lhs, Rhs &&rhs) const
RETURN(lib::forward<Lhs>(lhs) >= lib::forward<Rhs>(rhs))
};
#endif
} // namespace cpp14
inline namespace cpp17 {
// <type_traits>
template <bool B>
using bool_constant = std::integral_constant<bool, B>;
template <typename...>
struct voider : identity<void> {};
template <typename... Ts>
using void_t = typename voider<Ts...>::type;
namespace detail {
namespace swappable {
using std::swap;
template <typename T>
struct is_swappable_impl {
private:
template <typename U,
typename = decltype(swap(std::declval<U &>(),
std::declval<U &>()))>
inline static std::true_type test(int);
template <typename U>
inline static std::false_type test(...);
public:
using type = decltype(test<T>(0));
};
template <typename T>
using is_swappable = typename is_swappable_impl<T>::type;
template <typename T, bool = is_swappable<T>::value>
struct is_nothrow_swappable {
static constexpr bool value =
noexcept(swap(std::declval<T &>(), std::declval<T &>()));
};
template <typename T>
struct is_nothrow_swappable<T, false> : std::false_type {};
} // namespace swappable
} // namespace detail
template <typename T>
using is_swappable = detail::swappable::is_swappable<T>;
template <typename T>
using is_nothrow_swappable = detail::swappable::is_nothrow_swappable<T>;
// <functional>
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable : 4100)
#endif
template <typename F, typename... As>
inline constexpr auto invoke(F &&f, As &&... as)
RETURN(lib::forward<F>(f)(lib::forward<As>(as)...))
#ifdef _MSC_VER
#pragma warning(pop)
#endif
template <typename B, typename T, typename D>
inline constexpr auto invoke(T B::*pmv, D &&d)
RETURN(lib::forward<D>(d).*pmv)
template <typename Pmv, typename Ptr>
inline constexpr auto invoke(Pmv pmv, Ptr &&ptr)
RETURN((*lib::forward<Ptr>(ptr)).*pmv)
template <typename B, typename T, typename D, typename... As>
inline constexpr auto invoke(T B::*pmf, D &&d, As &&... as)
RETURN((lib::forward<D>(d).*pmf)(lib::forward<As>(as)...))
template <typename Pmf, typename Ptr, typename... As>
inline constexpr auto invoke(Pmf pmf, Ptr &&ptr, As &&... as)
RETURN(((*lib::forward<Ptr>(ptr)).*pmf)(lib::forward<As>(as)...))
namespace detail {
template <typename Void, typename, typename...>
struct invoke_result {};
template <typename F, typename... Args>
struct invoke_result<void_t<decltype(lib::invoke(
std::declval<F>(), std::declval<Args>()...))>,
F,
Args...>
: identity<decltype(
lib::invoke(std::declval<F>(), std::declval<Args>()...))> {};
} // namespace detail
template <typename F, typename... Args>
using invoke_result = detail::invoke_result<void, F, Args...>;
template <typename F, typename... Args>
using invoke_result_t = typename invoke_result<F, Args...>::type;
namespace detail {
template <typename Void, typename, typename...>
struct is_invocable : std::false_type {};
template <typename F, typename... Args>
struct is_invocable<void_t<invoke_result_t<F, Args...>>, F, Args...>
: std::true_type {};
template <typename Void, typename, typename, typename...>
struct is_invocable_r : std::false_type {};
template <typename R, typename F, typename... Args>
struct is_invocable_r<void_t<invoke_result_t<F, Args...>>,
R,
F,
Args...>
: std::is_convertible<invoke_result_t<F, Args...>, R> {};
} // namespace detail
template <typename F, typename... Args>
using is_invocable = detail::is_invocable<void, F, Args...>;
template <typename R, typename F, typename... Args>
using is_invocable_r = detail::is_invocable_r<void, R, F, Args...>;
// <memory>
#ifdef MPARK_BUILTIN_ADDRESSOF
template <typename T>
inline constexpr T *addressof(T &arg) {
return __builtin_addressof(arg);
}
#else
namespace detail {
namespace has_addressof_impl {
struct fail;
template <typename T>
inline fail operator&(T &&);
template <typename T>
inline static constexpr bool impl() {
return (std::is_class<T>::value || std::is_union<T>::value) &&
!std::is_same<decltype(&std::declval<T &>()), fail>::value;
}
} // namespace has_addressof_impl
template <typename T>
using has_addressof = bool_constant<has_addressof_impl::impl<T>()>;
template <typename T>
inline constexpr T *addressof(T &arg, std::true_type) {
return std::addressof(arg);
}
template <typename T>
inline constexpr T *addressof(T &arg, std::false_type) {
return &arg;
}
} // namespace detail
template <typename T>
inline constexpr T *addressof(T &arg) {
return detail::addressof(arg, detail::has_addressof<T>{});
}
#endif
template <typename T>
inline constexpr T *addressof(const T &&) = delete;
} // namespace cpp17
template <typename T>
struct remove_all_extents : identity<T> {};
template <typename T, std::size_t N>
struct remove_all_extents<array<T, N>> : remove_all_extents<T> {};
template <typename T>
using remove_all_extents_t = typename remove_all_extents<T>::type;
template <std::size_t N>
using size_constant = std::integral_constant<std::size_t, N>;
template <bool... Bs>
using bool_sequence = integer_sequence<bool, Bs...>;
template <std::size_t I, typename T>
struct indexed_type : size_constant<I>, identity<T> {};
template <bool... Bs>
using all =
std::is_same<bool_sequence<true, Bs...>, bool_sequence<Bs..., true>>;
#ifdef MPARK_TYPE_PACK_ELEMENT
template <std::size_t I, typename... Ts>
using type_pack_element_t = __type_pack_element<I, Ts...>;
#else
template <std::size_t I, typename... Ts>
struct type_pack_element_impl {
private:
template <typename>
struct set;
template <std::size_t... Is>
struct set<index_sequence<Is...>> : indexed_type<Is, Ts>... {};
template <typename T>
inline static std::enable_if<true, T> impl(indexed_type<I, T>);
inline static std::enable_if<false> impl(...);
public:
using type = decltype(impl(set<index_sequence_for<Ts...>>{}));
};
template <std::size_t I, typename... Ts>
using type_pack_element = typename type_pack_element_impl<I, Ts...>::type;
template <std::size_t I, typename... Ts>
using type_pack_element_t = typename type_pack_element<I, Ts...>::type;
#endif
#ifdef MPARK_TRIVIALITY_TYPE_TRAITS
template <typename T>
using is_trivially_copy_constructible =
std::is_trivially_copy_constructible<T>;
template <typename T>
using is_trivially_move_constructible =
std::is_trivially_move_constructible<T>;
template <typename T>
using is_trivially_copy_assignable = std::is_trivially_copy_assignable<T>;
template <typename T>
using is_trivially_move_assignable = std::is_trivially_move_assignable<T>;
#else
template <typename T>
struct is_trivially_copy_constructible
: bool_constant<
std::is_copy_constructible<T>::value && __has_trivial_copy(T)> {};
template <typename T>
struct is_trivially_move_constructible : bool_constant<__is_trivial(T)> {};
template <typename T>
struct is_trivially_copy_assignable
: bool_constant<
std::is_copy_assignable<T>::value && __has_trivial_assign(T)> {};
template <typename T>
struct is_trivially_move_assignable : bool_constant<__is_trivial(T)> {};
#endif
} // namespace lib
} // namespace mpark
#undef RETURN
#endif // MPARK_LIB_HPP
