470 lines
21 KiB
C++
470 lines
21 KiB
C++
#pragma once
|
|
|
|
#include "CoreTypes.h"
|
|
#include "Templates/Invoke.h"
|
|
#include "Templates/Utility.h"
|
|
#include "Templates/TypeHash.h"
|
|
#include "TypeTraits/TypeTraits.h"
|
|
#include "Memory/MemoryOperator.h"
|
|
#include "Miscellaneous/Compare.h"
|
|
#include "Miscellaneous/AssertionMacros.h"
|
|
|
|
NAMESPACE_REDCRAFT_BEGIN
|
|
NAMESPACE_MODULE_BEGIN(Redcraft)
|
|
NAMESPACE_MODULE_BEGIN(Utility)
|
|
|
|
template <typename... Ts> requires (true && ... && CDestructible<Ts>)
|
|
class TVariant;
|
|
|
|
NAMESPACE_PRIVATE_BEGIN
|
|
|
|
template <typename T > struct TIsTVariant : FFalse { };
|
|
template <typename... Ts> struct TIsTVariant<TVariant<Ts...>> : FTrue { };
|
|
|
|
template <typename TupleType>
|
|
struct TVariantNumImpl;
|
|
|
|
template <typename... Ts>
|
|
struct TVariantNumImpl<TVariant<Ts...>> : TConstant<size_t, sizeof...(Ts)> { };
|
|
|
|
template <typename... Ts>
|
|
struct TVariantNumImpl<const TVariant<Ts...>> : TConstant<size_t, sizeof...(Ts)> { };
|
|
|
|
template <typename... Ts>
|
|
struct TVariantNumImpl<volatile TVariant<Ts...>> : TConstant<size_t, sizeof...(Ts)> { };
|
|
|
|
template <typename... Ts>
|
|
struct TVariantNumImpl<const volatile TVariant<Ts...>> : TConstant<size_t, sizeof...(Ts)> { };
|
|
|
|
template <typename T, typename TupleType>
|
|
struct TVariantIndexImpl;
|
|
|
|
template <typename T, typename U, typename... Ts>
|
|
struct TVariantIndexImpl<T, TVariant<U, Ts...>> : TConstant<size_t, TVariantIndexImpl<T, TVariant<Ts...>>::Value + 1>
|
|
{
|
|
static_assert(sizeof...(Ts) != 0, "Non-existent types in variant");
|
|
};
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantIndexImpl<T, TVariant<T, Ts...>> : TConstant<size_t, 0>
|
|
{
|
|
static_assert((true && ... && !CSameAs<T, Ts>), "Duplicate type in variant");
|
|
};
|
|
|
|
template <typename T>
|
|
struct TVariantIndexImpl<T, TVariant<>> : TConstant<size_t, INDEX_NONE> { };
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantIndexImpl<T, const TVariant<Ts...>> : TVariantIndexImpl<T, TVariant<Ts...>> { };
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantIndexImpl<T, volatile TVariant<Ts...>> : TVariantIndexImpl<T, TVariant<Ts...>> { };
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantIndexImpl<T, const volatile TVariant<Ts...>> : TVariantIndexImpl<T, TVariant<Ts...>> { };
|
|
|
|
template <size_t I, typename TupleType>
|
|
struct TVariantAlternativeImpl;
|
|
|
|
template <size_t I, typename T, typename... Ts>
|
|
struct TVariantAlternativeImpl<I, TVariant<T, Ts...>>
|
|
{
|
|
static_assert(I < sizeof...(Ts) + 1, "Invalid index in variant");
|
|
using Type = TVariantAlternativeImpl<I - 1, TVariant<Ts...>>::Type;
|
|
};
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantAlternativeImpl<0, TVariant<T, Ts...>> { using Type = T; };
|
|
|
|
template <size_t I, typename... Ts>
|
|
struct TVariantAlternativeImpl<I, TVariant<Ts...>> { };
|
|
|
|
template <>
|
|
struct TVariantAlternativeImpl<0, TVariant<>> { };
|
|
|
|
template <size_t I, typename... Ts>
|
|
struct TVariantAlternativeImpl<I, const TVariant<Ts...>> { using Type = TAddConst<typename TVariantAlternativeImpl<I, TVariant<Ts...>>::Type>; };
|
|
|
|
template <size_t I, typename... Ts>
|
|
struct TVariantAlternativeImpl<I, volatile TVariant<Ts...>> { using Type = TAddVolatile<typename TVariantAlternativeImpl<I, TVariant<Ts...>>::Type>; };
|
|
|
|
template <size_t I, typename... Ts>
|
|
struct TVariantAlternativeImpl<I, const volatile TVariant<Ts...>> { using Type = TAddCV<typename TVariantAlternativeImpl<I, TVariant<Ts...>>::Type>; };
|
|
|
|
template <typename T, typename... Ts>
|
|
struct TVariantSelectedType;
|
|
|
|
template <typename T, typename U, typename... Ts>
|
|
struct TVariantSelectedType<T, U, Ts...>
|
|
{
|
|
using TypeAlternativeA = TConditional<CConstructibleFrom<U, T&&>, U, void>;
|
|
using TypeAlternativeB = typename TVariantSelectedType<T, Ts...>::Type;
|
|
|
|
using Type = TConditional<CSameAs<TRemoveCVRef<TypeAlternativeA>, void>, TypeAlternativeB,
|
|
TConditional<CSameAs<TRemoveCVRef<TypeAlternativeB>, void>, TypeAlternativeA,
|
|
TConditional<CSameAs<TRemoveCVRef<TypeAlternativeB>, TRemoveCVRef<T>>, TypeAlternativeB, TypeAlternativeA>>>;
|
|
|
|
// 0 - Type not found
|
|
// 1 - Same type found
|
|
// 2 - Multiple types found
|
|
// 3 - The type found
|
|
static constexpr uint8 Flag = CSameAs<TRemoveCVRef<Type>, void> ? 0 :
|
|
CSameAs<TRemoveCVRef<TypeAlternativeA>, TRemoveCVRef<TypeAlternativeB>> ? 2 :
|
|
CSameAs<TRemoveCVRef< Type>, TRemoveCVRef< T>> ? 1 :
|
|
!CSameAs<TRemoveCVRef<TypeAlternativeA>, void> && !CSameAs<TypeAlternativeB, void> ? 2 : 3;
|
|
|
|
static constexpr bool Value = Flag & 1;
|
|
|
|
};
|
|
|
|
template <typename T>
|
|
struct TVariantSelectedType<T>
|
|
{
|
|
static constexpr uint8 Flag = 0;
|
|
using Type = void;
|
|
};
|
|
|
|
NAMESPACE_PRIVATE_END
|
|
|
|
template <typename T>
|
|
concept CTVariant = NAMESPACE_PRIVATE::TIsTVariant<T>::Value;
|
|
|
|
template <typename VariantType>
|
|
inline constexpr size_t TVariantNum = NAMESPACE_PRIVATE::TVariantNumImpl<VariantType>::Value;
|
|
|
|
template <typename T, typename VariantType>
|
|
inline constexpr size_t TVariantIndex = NAMESPACE_PRIVATE::TVariantIndexImpl<T, VariantType>::Value;
|
|
|
|
template <size_t I, typename VariantType>
|
|
using TVariantAlternative = typename NAMESPACE_PRIVATE::TVariantAlternativeImpl<I, VariantType>::Type;
|
|
|
|
template <typename... Ts> requires (true && ... && CDestructible<Ts>)
|
|
class TVariant
|
|
{
|
|
public:
|
|
|
|
constexpr TVariant() : TypeIndex(0xFF) { };
|
|
|
|
constexpr TVariant(FInvalid) : TVariant() { };
|
|
|
|
constexpr TVariant(const TVariant& InValue) requires (true && ... && CCopyConstructible<Ts>)
|
|
: TypeIndex(static_cast<uint8>(InValue.GetIndex()))
|
|
{
|
|
if (IsValid()) CopyConstructImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
}
|
|
|
|
constexpr TVariant(TVariant&& InValue) requires (true && ... && CMoveConstructible<Ts>)
|
|
: TypeIndex(static_cast<uint8>(InValue.GetIndex()))
|
|
{
|
|
if (IsValid()) MoveConstructImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
}
|
|
|
|
template <size_t I, typename... ArgTypes> requires (I < sizeof...(Ts))
|
|
&& CConstructibleFrom<TVariantAlternative<I, TVariant<Ts...>>, ArgTypes...>
|
|
constexpr explicit TVariant(TInPlaceIndex<I>, ArgTypes&&... Args)
|
|
: TypeIndex(I)
|
|
{
|
|
using SelectedType = TVariantAlternative<I, TVariant<Ts...>>;
|
|
new(&Value) SelectedType(Forward<ArgTypes>(Args)...);
|
|
}
|
|
|
|
template <typename T, typename... ArgTypes> requires CConstructibleFrom<T, ArgTypes...>
|
|
constexpr explicit TVariant(TInPlaceType<T>, ArgTypes&&... Args)
|
|
: TVariant(InPlaceIndex<TVariantIndex<T, TVariant<Ts...>>>, Forward<ArgTypes>(Args)...)
|
|
{ }
|
|
|
|
template <typename T> requires NAMESPACE_PRIVATE::TVariantSelectedType<TRemoveReference<T>, Ts...>::Value
|
|
&& (!CTInPlaceType<TRemoveCVRef<T>>) && (!CTInPlaceIndex<TRemoveCVRef<T>>)
|
|
&& (!CSameAs<TRemoveCVRef<T>, TVariant>)
|
|
constexpr TVariant(T&& InValue) : TVariant(InPlaceType<typename NAMESPACE_PRIVATE::TVariantSelectedType<TRemoveReference<T>, Ts...>::Type>, Forward<T>(InValue))
|
|
{ }
|
|
|
|
constexpr ~TVariant()
|
|
{
|
|
if constexpr (!(true && ... && CTriviallyDestructible<Ts>)) Reset();
|
|
}
|
|
|
|
constexpr TVariant& operator=(const TVariant& InValue) requires (true && ... && (CCopyConstructible<Ts> && CCopyAssignable<Ts>))
|
|
{
|
|
if (&InValue == this) return *this;
|
|
|
|
if (!InValue.IsValid())
|
|
{
|
|
Reset();
|
|
return *this;
|
|
}
|
|
|
|
if (GetIndex() == InValue.GetIndex()) CopyAssignImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
else
|
|
{
|
|
Reset();
|
|
CopyConstructImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
TypeIndex = static_cast<uint8>(InValue.GetIndex());
|
|
}
|
|
|
|
return *this;
|
|
}
|
|
|
|
constexpr TVariant& operator=(TVariant&& InValue) requires (true && ... && (CMoveConstructible<Ts> && CMoveAssignable<Ts>))
|
|
{
|
|
if (&InValue == this) return *this;
|
|
|
|
if (!InValue.IsValid())
|
|
{
|
|
Reset();
|
|
return *this;
|
|
}
|
|
|
|
if (GetIndex() == InValue.GetIndex()) MoveAssignImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
else
|
|
{
|
|
Reset();
|
|
MoveConstructImpl[InValue.GetIndex()](&Value, &InValue.Value);
|
|
TypeIndex = static_cast<uint8>(InValue.GetIndex());
|
|
}
|
|
|
|
return *this;
|
|
}
|
|
|
|
template <typename T> requires NAMESPACE_PRIVATE::TVariantSelectedType<TRemoveReference<T>, Ts...>::Value
|
|
constexpr TVariant& operator=(T&& InValue)
|
|
{
|
|
using SelectedType = typename NAMESPACE_PRIVATE::TVariantSelectedType<TRemoveReference<T>, Ts...>::Type;
|
|
|
|
if (GetIndex() == TVariantIndex<SelectedType, TVariant<Ts...>>) GetValue<SelectedType>() = Forward<T>(InValue);
|
|
else
|
|
{
|
|
Reset();
|
|
new(&Value) SelectedType(Forward<T>(InValue));
|
|
TypeIndex = TVariantIndex<SelectedType, TVariant<Ts...>>;
|
|
}
|
|
|
|
return *this;
|
|
}
|
|
|
|
template <size_t I, typename... ArgTypes> requires (I < sizeof...(Ts))
|
|
&& CConstructibleFrom<TVariantAlternative<I, TVariant<Ts...>>, ArgTypes...>
|
|
constexpr TVariantAlternative<I, TVariant<Ts...>>& Emplace(ArgTypes&&... Args)
|
|
{
|
|
Reset();
|
|
|
|
using SelectedType = TVariantAlternative<I, TVariant<Ts...>>;
|
|
SelectedType* Result = new(&Value) SelectedType(Forward<ArgTypes>(Args)...);
|
|
TypeIndex = I;
|
|
|
|
return *Result;
|
|
}
|
|
|
|
template <typename T, typename... ArgTypes> requires CConstructibleFrom<T, ArgTypes...>
|
|
constexpr T& Emplace(ArgTypes&&... Args)
|
|
{
|
|
return Emplace<TVariantIndex<T, TVariant<Ts...>>>(Forward<ArgTypes>(Args)...);
|
|
}
|
|
|
|
constexpr const type_info& GetTypeInfo() const { return IsValid() ? *TypeInfos[GetIndex()] : typeid(void); }
|
|
|
|
constexpr size_t GetIndex() const { return TypeIndex != 0xFF ? TypeIndex : INDEX_NONE; }
|
|
constexpr bool IsValid() const { return TypeIndex != 0xFF; }
|
|
constexpr explicit operator bool() const { return TypeIndex != 0xFF; }
|
|
|
|
template <size_t I> constexpr bool HoldsAlternative() const { return IsValid() ? GetIndex() == I : false; }
|
|
template <typename T> constexpr bool HoldsAlternative() const { return IsValid() ? GetIndex() == TVariantIndex<T, TVariant<Ts...>> : false; }
|
|
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) GetValue() & { checkf(HoldsAlternative<I>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast< TVariantAlternative<I, TVariant<Ts...>>*>(&Value); }
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) GetValue() && { checkf(HoldsAlternative<I>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast< TVariantAlternative<I, TVariant<Ts...>>*>(&Value)); }
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) GetValue() const& { checkf(HoldsAlternative<I>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast<const TVariantAlternative<I, TVariant<Ts...>>*>(&Value); }
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) GetValue() const&& { checkf(HoldsAlternative<I>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast<const TVariantAlternative<I, TVariant<Ts...>>*>(&Value)); }
|
|
|
|
template <typename T> constexpr decltype(auto) GetValue() & { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast< T*>(&Value); }
|
|
template <typename T> constexpr decltype(auto) GetValue() && { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast< T*>(&Value)); }
|
|
template <typename T> constexpr decltype(auto) GetValue() const& { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast<const T*>(&Value); }
|
|
template <typename T> constexpr decltype(auto) GetValue() const&& { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TVariant. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast<const T*>(&Value)); }
|
|
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) Get( TVariantAlternative<I, TVariant<Ts...>>& DefaultValue) & { return HoldsAlternative<I>() ? GetValue<I>() : DefaultValue; }
|
|
template <size_t I> requires (I < sizeof...(Ts)) constexpr decltype(auto) Get(const TVariantAlternative<I, TVariant<Ts...>>& DefaultValue) const& { return HoldsAlternative<I>() ? GetValue<I>() : DefaultValue; }
|
|
|
|
template <typename T> constexpr decltype(auto) Get( T& DefaultValue) & { return HoldsAlternative<T>() ? GetValue<T>() : DefaultValue; }
|
|
template <typename T> constexpr decltype(auto) Get(const T& DefaultValue) const& { return HoldsAlternative<T>() ? GetValue<T>() : DefaultValue; }
|
|
|
|
template <typename F> requires (true && ... && CInvocable<F, Ts>)
|
|
FORCEINLINE decltype(auto) Visit(F&& Func) &
|
|
{
|
|
checkf(IsValid(), TEXT("It is an error to call Visit() on an wrong TVariant. Please either check IsValid()."));
|
|
|
|
using ReturnType = TCommonType<TInvokeResult<F, Ts>...>;
|
|
|
|
using FInvokeImpl = ReturnType(*)(F&&, void*);
|
|
static constexpr FInvokeImpl InvokeImpl[] = { [](F&& Func, void* This) -> ReturnType { return InvokeResult<ReturnType>(Forward<F>(Func), *reinterpret_cast<Ts*>(This)); }... };
|
|
|
|
return InvokeImpl[GetIndex()](Forward<F>(Func), &Value);
|
|
}
|
|
|
|
template <typename F> requires (true && ... && CInvocable<F, Ts>)
|
|
FORCEINLINE decltype(auto) Visit(F&& Func) &&
|
|
{
|
|
checkf(IsValid(), TEXT("It is an error to call Visit() on an wrong TVariant. Please either check IsValid()."));
|
|
|
|
using ReturnType = TCommonType<TInvokeResult<F, Ts>...>;
|
|
|
|
using FInvokeImpl = ReturnType(*)(F&&, void*);
|
|
static constexpr FInvokeImpl InvokeImpl[] = { [](F&& Func, void* This) -> ReturnType { return InvokeResult<ReturnType>(Forward<F>(Func), MoveTemp(*reinterpret_cast<Ts*>(This))); }... };
|
|
|
|
return InvokeImpl[GetIndex()](Forward<F>(Func), &Value);
|
|
}
|
|
|
|
template <typename F> requires (true && ... && CInvocable<F, Ts>)
|
|
FORCEINLINE decltype(auto) Visit(F&& Func) const&
|
|
{
|
|
checkf(IsValid(), TEXT("It is an error to call Visit() on an wrong TVariant. Please either check IsValid()."));
|
|
|
|
using ReturnType = TCommonType<TInvokeResult<F, Ts>...>;
|
|
|
|
using FInvokeImpl = ReturnType(*)(F&&, const void*);
|
|
static constexpr FInvokeImpl InvokeImpl[] = { [](F&& Func, const void* This) -> ReturnType { return InvokeResult<ReturnType>(Forward<F>(Func), *reinterpret_cast<const Ts*>(This)); }... };
|
|
|
|
return InvokeImpl[GetIndex()](Forward<F>(Func), &Value);
|
|
}
|
|
|
|
template <typename F> requires (true && ... && CInvocable<F, Ts>)
|
|
FORCEINLINE decltype(auto) Visit(F&& Func) const&&
|
|
{
|
|
checkf(IsValid(), TEXT("It is an error to call Visit() on an wrong TVariant. Please either check IsValid()."));
|
|
|
|
using ReturnType = TCommonType<TInvokeResult<F, Ts>...>;
|
|
|
|
using FInvokeImpl = ReturnType(*)(F&&, const void*);
|
|
static constexpr FInvokeImpl InvokeImpl[] = { [](F&& Func, const void* This) -> ReturnType { return InvokeResult<ReturnType>(Forward<F>(Func), MoveTemp(*reinterpret_cast<const Ts*>(This))); }... };
|
|
|
|
return InvokeImpl[GetIndex()](Forward<F>(Func), &Value);
|
|
}
|
|
|
|
template <typename R, typename F> requires (true && ... && CInvocableResult<R, F, Ts>)
|
|
FORCEINLINE R Visit(F&& Func) & { return Visit(Forward<F>(Func)); }
|
|
|
|
template <typename R, typename F> requires (true && ... && CInvocableResult<R, F, Ts>)
|
|
FORCEINLINE R Visit(F&& Func) && { return MoveTemp(*this).Visit(Forward<F>(Func)); }
|
|
|
|
template <typename R, typename F> requires (true && ... && CInvocableResult<R, F, Ts>)
|
|
FORCEINLINE R Visit(F&& Func) const& { return Visit(Forward<F>(Func)); }
|
|
|
|
template <typename R, typename F> requires (true && ... && CInvocableResult<R, F, Ts>)
|
|
FORCEINLINE R Visit(F&& Func) const&& { return MoveTemp(*this).Visit(Forward<F>(Func)); }
|
|
|
|
constexpr void Reset()
|
|
{
|
|
if (GetIndex() == INDEX_NONE) return;
|
|
|
|
if constexpr (!(true && ... && CTriviallyDestructible<Ts>))
|
|
{
|
|
DestroyImpl[GetIndex()](&Value);
|
|
}
|
|
|
|
TypeIndex = static_cast<uint8>(INDEX_NONE);
|
|
}
|
|
|
|
constexpr size_t GetTypeHash() const requires (true && ... && CHashable<Ts>)
|
|
{
|
|
if (!IsValid()) return 114514;
|
|
|
|
using NAMESPACE_REDCRAFT::GetTypeHash;
|
|
|
|
using FHashImpl = size_t(*)(const void*);
|
|
constexpr FHashImpl HashImpl[] = { [](const void* This) -> size_t { return GetTypeHash(*reinterpret_cast<const Ts*>(This)); }... };
|
|
|
|
return HashCombine(GetTypeHash(GetIndex()), HashImpl[GetIndex()](&Value));
|
|
}
|
|
|
|
constexpr void Swap(TVariant& InValue) requires (true && ... && (CMoveConstructible<Ts> && CSwappable<Ts>))
|
|
{
|
|
if (!IsValid() && !InValue.IsValid()) return;
|
|
|
|
if (IsValid() && !InValue.IsValid())
|
|
{
|
|
InValue = MoveTemp(*this);
|
|
Reset();
|
|
return;
|
|
}
|
|
|
|
if (InValue.IsValid() && !IsValid())
|
|
{
|
|
*this = MoveTemp(InValue);
|
|
InValue.Reset();
|
|
return;
|
|
}
|
|
|
|
if (GetIndex() == InValue.GetIndex())
|
|
{
|
|
using NAMESPACE_REDCRAFT::Swap;
|
|
|
|
using FSwapImpl = void(*)(void*, void*);
|
|
constexpr FSwapImpl SwapImpl[] = { [](void* A, void* B) { Swap(*reinterpret_cast<Ts*>(A), *reinterpret_cast<Ts*>(B)); }... };
|
|
|
|
SwapImpl[GetIndex()](&Value, &InValue.Value);
|
|
|
|
return;
|
|
}
|
|
|
|
TVariant Temp = MoveTemp(*this);
|
|
*this = MoveTemp(InValue);
|
|
InValue = MoveTemp(Temp);
|
|
}
|
|
|
|
private:
|
|
|
|
static constexpr const type_info* TypeInfos[] = { &typeid(Ts)... };
|
|
|
|
using FCopyConstructImpl = void(*)(void*, const void*);
|
|
using FMoveConstructImpl = void(*)(void*, void*);
|
|
using FCopyAssignImpl = void(*)(void*, const void*);
|
|
using FMoveAssignImpl = void(*)(void*, void*);
|
|
using FDestroyImpl = void(*)(void* );
|
|
|
|
static constexpr FCopyConstructImpl CopyConstructImpl[] = { [](void* A, const void* B) { if constexpr (requires(Ts* A, const Ts* B) { Memory::CopyConstruct (A, B); }) Memory::CopyConstruct (reinterpret_cast<Ts*>(A), reinterpret_cast<const Ts*>(B)); else checkf(false, TEXT("The type '%s' is not copy constructible."), typeid(Ts).name()); }... };
|
|
static constexpr FMoveConstructImpl MoveConstructImpl[] = { [](void* A, void* B) { if constexpr (requires(Ts* A, Ts* B) { Memory::MoveConstruct (A, B); }) Memory::MoveConstruct (reinterpret_cast<Ts*>(A), reinterpret_cast< Ts*>(B)); else checkf(false, TEXT("The type '%s' is not move constructible."), typeid(Ts).name()); }... };
|
|
static constexpr FCopyAssignImpl CopyAssignImpl[] = { [](void* A, const void* B) { if constexpr (requires(Ts* A, const Ts* B) { Memory::CopyAssign (A, B); }) Memory::CopyAssign (reinterpret_cast<Ts*>(A), reinterpret_cast<const Ts*>(B)); else checkf(false, TEXT("The type '%s' is not copy assignable."), typeid(Ts).name()); }... };
|
|
static constexpr FMoveAssignImpl MoveAssignImpl[] = { [](void* A, void* B) { if constexpr (requires(Ts* A, Ts* B) { Memory::MoveAssign (A, B); }) Memory::MoveAssign (reinterpret_cast<Ts*>(A), reinterpret_cast< Ts*>(B)); else checkf(false, TEXT("The type '%s' is not move assignable."), typeid(Ts).name()); }... };
|
|
static constexpr FDestroyImpl DestroyImpl[] = { [](void* A ) { if constexpr (requires(Ts* A ) { Memory::Destruct (A ); }) Memory::Destruct (reinterpret_cast<Ts*>(A) ); else checkf(false, TEXT("The type '%s' is not destructible."), typeid(Ts).name()); }... };
|
|
|
|
TAlignedUnion<1, Ts...> Value;
|
|
uint8 TypeIndex;
|
|
|
|
friend constexpr bool operator==(const TVariant& LHS, const TVariant& RHS) requires (true && ... && CEqualityComparable<Ts>)
|
|
{
|
|
if (LHS.GetIndex() != RHS.GetIndex()) return false;
|
|
if (LHS.IsValid() == false) return true;
|
|
|
|
using FCompareImpl = bool(*)(const void*, const void*);
|
|
constexpr FCompareImpl CompareImpl[] = { [](const void* LHS, const void* RHS) -> bool { return *reinterpret_cast<const Ts*>(LHS) == *reinterpret_cast<const Ts*>(RHS); }... };
|
|
|
|
return CompareImpl[LHS.GetIndex()](&LHS.Value, &RHS.Value);
|
|
}
|
|
|
|
friend constexpr partial_ordering operator<=>(const TVariant& LHS, const TVariant& RHS) requires (true && ... && CSynthThreeWayComparable<Ts>)
|
|
{
|
|
if (LHS.GetIndex() != RHS.GetIndex()) return partial_ordering::unordered;
|
|
if (LHS.IsValid() == false) return partial_ordering::equivalent;
|
|
|
|
using FCompareImpl = partial_ordering(*)(const void*, const void*);
|
|
constexpr FCompareImpl CompareImpl[] = { [](const void* LHS, const void* RHS) -> partial_ordering { return SynthThreeWayCompare(*reinterpret_cast<const Ts*>(LHS), *reinterpret_cast<const Ts*>(RHS)); }...};
|
|
|
|
return CompareImpl[LHS.GetIndex()](&LHS.Value, &RHS.Value);
|
|
}
|
|
|
|
};
|
|
|
|
template <typename T, typename... Ts> requires (!CSameAs<T, TVariant<Ts...>>) && CEqualityComparable<T>
|
|
constexpr bool operator==(const TVariant<Ts...>& LHS, const T& RHS)
|
|
{
|
|
return LHS.template HoldsAlternative<T>() ? LHS.template GetValue<T>() == RHS : false;
|
|
}
|
|
|
|
template <typename... Ts>
|
|
constexpr bool operator==(const TVariant<Ts...>& LHS, FInvalid)
|
|
{
|
|
return !LHS.IsValid();
|
|
}
|
|
|
|
NAMESPACE_MODULE_END(Utility)
|
|
NAMESPACE_MODULE_END(Redcraft)
|
|
NAMESPACE_REDCRAFT_END
|