libostd/octa/internal/tuple.hh

281 lines
8.8 KiB
C++

/* Some tuple internals for inclusion from various headers. Partially
* taken from the libc++ project.
*
* This file is part of OctaSTD. See COPYING.md for futher information.
*/
#ifndef OCTA_INTERNAL_TUPLE_HH
#define OCTA_INTERNAL_TUPLE_HH
#include "octa/types.hh"
#include "octa/type_traits.hh"
namespace ostd {
template<typename ...A> class Tuple;
template<typename T, typename U> struct Pair;
template<typename T, Size I> struct Array;
/* tuple size */
template<typename T> struct TupleSize;
template<typename T> struct TupleSize<const T>: public TupleSize<T> {};
template<typename T> struct TupleSize<volatile T>: public TupleSize<T> {};
template<typename T> struct TupleSize<const volatile T>: public TupleSize<T> {};
/* tuple element */
template<Size I, typename T> struct TupleElementBase;
template<Size I, typename T>
struct TupleElementBase<I, const T> {
using Type = AddConst<typename TupleElementBase<I, T>::Type>;
};
template<Size I, typename T>
struct TupleElementBase<I, volatile T> {
using Type = AddVolatile<typename TupleElementBase<I, T>::Type>;
};
template<Size I, typename T>
struct TupleElementBase<I, const volatile T> {
using Type = AddCv<typename TupleElementBase<I, T>::Type>;
};
template<Size I, typename T>
using TupleElement = typename TupleElementBase<I, T>::Type;
/* is tuple-like */
template<typename T> struct IsTupleLike: False {};
template<typename T> struct IsTupleLike<const T>: IsTupleLike<T> {};
template<typename T> struct IsTupleLike<volatile T>: IsTupleLike<T> {};
template<typename T> struct IsTupleLike<const volatile T>: IsTupleLike<T> {};
/* tuple specializations */
template<typename ...A> struct IsTupleLike<Tuple<A...>>: True {};
template<Size I, typename ...A>
TupleElement<I, Tuple<A...>> &get(Tuple<A...> &);
template<Size I, typename ...A>
const TupleElement<I, Tuple<A...>> &get(const Tuple<A...> &);
template<Size I, typename ...A>
TupleElement<I, Tuple<A...>> &&get(Tuple<A...> &&);
/* pair specializations */
template<typename T, typename U> struct IsTupleLike<Pair<T, U>>: True {};
template<Size I, typename T, typename U>
TupleElement<I, Pair<T, U>> &get(Pair<T, U> &);
template<Size I, typename T, typename U>
const TupleElement<I, Pair<T, U>> &get(const Pair<T, U> &);
template<Size I, typename T, typename U>
TupleElement<I, Pair<T, U>> &&get(Pair<T, U> &&);
/* array specializations */
template<typename T, Size I> struct IsTupleLike<Array<T, I>>: True {};
template<Size I, typename T, Size S>
T &get(Array<T, S> &);
template<Size I, typename T, Size S>
const T &get(const Array<T, S> &);
template<Size I, typename T, Size S>
T &&get(Array<T, S> &&);
/* make tuple indices */
namespace detail {
template<Size ...> struct TupleIndices {};
template<Size S, typename T, Size E> struct MakeTupleIndicesBase;
template<Size S, Size ...I, Size E>
struct MakeTupleIndicesBase<S, TupleIndices<I...>, E> {
using Type = typename MakeTupleIndicesBase<S + 1,
TupleIndices<I..., S>, E>::Type;
};
template<Size E, Size ...I>
struct MakeTupleIndicesBase<E, TupleIndices<I...>, E> {
using Type = TupleIndices<I...>;
};
template<Size E, Size S>
struct MakeTupleIndicesImpl {
static_assert(S <= E, "MakeTupleIndices input error");
using Type = typename MakeTupleIndicesBase<S, TupleIndices<>, E>::Type;
};
template<Size E, Size S = 0>
using MakeTupleIndices = typename MakeTupleIndicesImpl<E, S>::Type;
}
/* tuple types */
namespace detail {
template<typename ...T> struct TupleTypes {};
}
template<Size I> struct TupleElementBase<I, detail::TupleTypes<>> {
public:
static_assert(I == 0, "TupleElement index out of range");
static_assert(I != 0, "TupleElement index out of range");
};
template<typename H, typename ...T>
struct TupleElementBase<0, detail::TupleTypes<H, T...>> {
public:
using Type = H;
};
template<Size I, typename H, typename ...T>
struct TupleElementBase<I, detail::TupleTypes<H, T...>> {
public:
using Type = typename TupleElementBase<I - 1,
detail::TupleTypes<T...>>::Type;
};
template<typename ...T> struct TupleSize<detail::TupleTypes<T...>>:
IntegralConstant<Size, sizeof...(T)> {};
template<typename ...T> struct IsTupleLike<detail::TupleTypes<T...>>: True {};
/* make tuple types */
namespace detail {
template<typename TT, typename T, Size S, Size E>
struct MakeTupleTypesBase;
template<typename ...TS, typename T, Size S, Size E>
struct MakeTupleTypesBase<TupleTypes<TS...>, T, S, E> {
using TR = RemoveReference<T>;
using Type = typename MakeTupleTypesBase<TupleTypes<TS...,
Conditional<IsLvalueReference<T>::value,
TupleElement<S, TR> &,
TupleElement<S, TR>>>, T, S + 1, E>::Type;
};
template<typename ...TS, typename T, Size E>
struct MakeTupleTypesBase<TupleTypes<TS...>, T, E, E> {
using Type = TupleTypes<TS...>;
};
template<typename T, Size E, Size S>
struct MakeTupleTypesImpl {
static_assert(S <= E, "MakeTupleTypes input error");
using Type = typename MakeTupleTypesBase<TupleTypes<>, T, S, E>::Type;
};
template<typename T, Size E = TupleSize<RemoveReference<T>>::value, Size S = 0>
using MakeTupleTypes = typename MakeTupleTypesImpl<T, E, S>::Type;
}
/* tuple convertible */
namespace detail {
template<typename, typename>
struct TupleConvertibleBase: False {};
template<typename T, typename ...TT, typename U, typename ...UU>
struct TupleConvertibleBase<TupleTypes<T, TT...>, TupleTypes<U, UU...>>:
IntegralConstant<bool, IsConvertible<T, U>::value &&
TupleConvertibleBase<TupleTypes<TT...>,
TupleTypes<UU...>>::value> {};
template<>
struct TupleConvertibleBase<TupleTypes<>, TupleTypes<>>: True {};
template<bool, typename, typename>
struct TupleConvertibleApply: False {};
template<typename T, typename U>
struct TupleConvertibleApply<true, T, U>: TupleConvertibleBase<
MakeTupleTypes<T>, MakeTupleTypes<U>
> {};
template<typename T, typename U, bool = IsTupleLike<RemoveReference<T>>::value,
bool = IsTupleLike<U>::value>
struct TupleConvertible: False {};
template<typename T, typename U>
struct TupleConvertible<T, U, true, true>: TupleConvertibleApply<
TupleSize<RemoveReference<T>>::value == TupleSize<U>::value, T, U
> {};
}
/* tuple constructible */
namespace detail {
template<typename, typename>
struct TupleConstructibleBase: False {};
template<typename T, typename ...TT, typename U, typename ...UU>
struct TupleConstructibleBase<TupleTypes<T, TT...>, TupleTypes<U, UU...>>:
IntegralConstant<bool, IsConstructible<U, T>::value &&
TupleConstructibleBase<TupleTypes<TT...>,
TupleTypes<UU...>>::value> {};
template<>
struct TupleConstructibleBase<TupleTypes<>, TupleTypes<>>: True {};
template<bool, typename, typename>
struct TupleConstructibleApply: False {};
template<typename T, typename U>
struct TupleConstructibleApply<true, T, U>: TupleConstructibleBase<
MakeTupleTypes<T>, MakeTupleTypes<U>
> {};
template<typename T, typename U, bool = IsTupleLike<RemoveReference<T>>::value,
bool = IsTupleLike<U>::value>
struct TupleConstructible: False {};
template<typename T, typename U>
struct TupleConstructible<T, U, true, true>: TupleConstructibleApply<
TupleSize<RemoveReference<T>>::value == TupleSize<U>::value, T, U
> {};
}
/* tuple assignable */
namespace detail {
template<typename, typename>
struct TupleAssignableBase: False {};
template<typename T, typename ...TT, typename U, typename ...UU>
struct TupleAssignableBase<TupleTypes<T, TT...>, TupleTypes<U, UU...>>:
IntegralConstant<bool, IsAssignable<U &, T>::value &&
TupleAssignableBase<TupleTypes<TT...>,
TupleTypes<UU...>>::value> {};
template<>
struct TupleAssignableBase<TupleTypes<>, TupleTypes<>>: True {};
template<bool, typename, typename>
struct TupleAssignableApply: False {};
template<typename T, typename U>
struct TupleAssignableApply<true, T, U>: TupleAssignableBase<
MakeTupleTypes<T>, MakeTupleTypes<U>
> {};
template<typename T, typename U, bool = IsTupleLike<RemoveReference<T>>::value,
bool = IsTupleLike<U>::value>
struct TupleAssignable: False {};
template<typename T, typename U>
struct TupleAssignable<T, U, true, true>: TupleAssignableApply<
TupleSize<RemoveReference<T>>::value == TupleSize<U>::value, T, U
> {};
}
} /* namespace ostd */
#endif