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#pragma once
#include <type_traits>
#include <utility>
#include <initializer_list>
#include "StarAlgorithm.hpp"
#include "StarMaybe.hpp"
namespace Star {
STAR_EXCEPTION(BadVariantCast, StarException);
STAR_EXCEPTION(BadVariantType, StarException);
typedef uint8_t VariantTypeIndex;
VariantTypeIndex const InvalidVariantType = 255;
namespace detail {
template <typename T, typename... Args>
struct HasType;
template <typename T>
struct HasType<T> : std::false_type {};
template <typename T, typename Head, typename... Args>
struct HasType<T, Head, Args...> {
static constexpr bool value = std::is_same<T, Head>::value || HasType<T, Args...>::value;
};
template <typename... Args>
struct IsNothrowMoveConstructible;
template <>
struct IsNothrowMoveConstructible<> : std::true_type {};
template <typename Head, typename... Args>
struct IsNothrowMoveConstructible<Head, Args...> {
static constexpr bool value = std::is_nothrow_move_constructible<Head>::value && IsNothrowMoveConstructible<Args...>::value;
};
template <typename... Args>
struct IsNothrowMoveAssignable;
template <>
struct IsNothrowMoveAssignable<> : std::true_type {};
template <typename Head, typename... Args>
struct IsNothrowMoveAssignable<Head, Args...> {
static constexpr bool value = std::is_nothrow_move_assignable<Head>::value && IsNothrowMoveAssignable<Args...>::value;
};
}
// Stack based variant type container that can be inhabited by one of a limited
// number of types.
template <typename FirstType, typename... RestTypes>
class Variant {
public:
template <typename T>
using ValidateType = typename std::enable_if<detail::HasType<T, FirstType, RestTypes...>::value, void>::type;
template <typename T, typename = ValidateType<T>>
static constexpr VariantTypeIndex typeIndexOf();
// If the first type has a default constructor, constructs an Variant which
// contains a default constructed value of that type.
Variant();
template <typename T, typename = ValidateType<T>>
Variant(T const& x);
template <typename T, typename = ValidateType<T>>
Variant(T&& x);
template <typename T, typename = ValidateType<T>, typename... Args,
typename std::enable_if< std::is_constructible<T, Args...>::value, int >::type = 0
>
Variant(std::in_place_type_t<T>, Args&&... args) {
new (&m_buffer) T(std::forward<Args>(args)...);
m_typeIndex = TypeIndex<T>::value;
}
template <typename T, typename U, typename = ValidateType<T>, typename... Args,
typename std::enable_if< std::is_constructible<T, std::initializer_list<U>&, Args...>::value, int >::type = 0
>
Variant(std::in_place_type_t<T>, std::initializer_list<U> il, Args&&... args) {
new (&m_buffer) T(il, std::forward<Args>(args)...);
m_typeIndex = TypeIndex<T>::value;
}
Variant(Variant const& x);
Variant(Variant&& x) noexcept(detail::IsNothrowMoveConstructible<FirstType, RestTypes...>::value);
~Variant();
// Implementations of operator= may invalidate the Variant if the copy or
// move constructor of the assigned value throws.
Variant& operator=(Variant const& x);
Variant& operator=(Variant&& x) noexcept(detail::IsNothrowMoveAssignable<FirstType, RestTypes...>::value);
template <typename T, typename = ValidateType<T>>
Variant& operator=(T const& x);
template <typename T, typename = ValidateType<T>>
Variant& operator=(T&& x);
// Returns true if this Variant contains the given type.
template <typename T, typename = ValidateType<T>>
bool is() const;
// get throws BadVariantCast on bad casts
template <typename T, typename = ValidateType<T>>
T const& get() const;
template <typename T, typename = ValidateType<T>>
T& get();
template <typename T, typename = ValidateType<T>>
Maybe<T> maybe() const;
// ptr() does not throw if this Variant does not hold the given type, instead
// simply returns nullptr.
template <typename T, typename = ValidateType<T>>
T const* ptr() const;
template <typename T, typename = ValidateType<T>>
T* ptr();
// Calls the given function with the type currently being held, and returns
// the value returned by that function. Will throw if this Variant has been
// invalidated.
template <typename Function>
decltype(auto) call(Function&& function);
template <typename Function>
decltype(auto) call(Function&& function) const;
// Returns an index for the held type, which can be passed into makeType to
// make this Variant hold a specific type. Returns InvalidVariantType if
// invalidated.
VariantTypeIndex typeIndex() const;
// Make this Variant hold a new default constructed type of the given type
// index. Can only be used if every alternative type has a default
// constructor. Throws if given an out of range type index or
// InvalidVariantType.
void makeType(VariantTypeIndex typeIndex);
// True if this Variant has been invalidated. If the copy or move
// constructor of a type throws an exception during assignment, there is no
// *good* way to ensure that the Variant has a valid type, so it may become
// invalidated. It is not possible to directly construct an invalidated
// Variant.
bool invalid() const;
// Requires that every type included in this Variant has operator==
bool operator==(Variant const& x) const;
bool operator!=(Variant const& x) const;
// Requires that every type included in this Variant has operator<
bool operator<(Variant const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator==(T const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator!=(T const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator<(T const& x) const;
private:
template <typename MatchType, VariantTypeIndex Index, typename... Rest>
struct LookupTypeIndex;
template <typename MatchType, VariantTypeIndex Index>
struct LookupTypeIndex<MatchType, Index> {
static VariantTypeIndex const value = InvalidVariantType;
};
template <typename MatchType, VariantTypeIndex Index, typename Head, typename... Rest>
struct LookupTypeIndex<MatchType, Index, Head, Rest...> {
static VariantTypeIndex const value = std::is_same<MatchType, Head>::value ? Index : LookupTypeIndex<MatchType, Index + 1, Rest...>::value;
};
template <typename MatchType>
struct TypeIndex {
static VariantTypeIndex const value = LookupTypeIndex<MatchType, 0, FirstType, RestTypes...>::value;
};
void destruct();
template <typename T>
void assign(T&& x);
template <typename Function, typename T>
decltype(auto) doCall(Function&& function);
template <typename Function, typename T1, typename T2, typename... TL>
decltype(auto) doCall(Function&& function);
template <typename Function, typename T>
decltype(auto) doCall(Function&& function) const;
template <typename Function, typename T1, typename T2, typename... TL>
decltype(auto) doCall(Function&& function) const;
template <typename First>
void doMakeType(VariantTypeIndex);
template <typename First, typename Second, typename... Rest>
void doMakeType(VariantTypeIndex typeIndex);
typename std::aligned_union<0, FirstType, RestTypes...>::type m_buffer;
VariantTypeIndex m_typeIndex = InvalidVariantType;
};
// A version of Variant that has always has a default "empty" state, useful
// when there is no good default type for a Variant but it needs to be default
// constructed, and is slightly more convenient than Maybe<Variant<Types...>>.
template <typename... Types>
class MVariant {
public:
template <typename T>
using ValidateType = typename std::enable_if<detail::HasType<T, Types...>::value, void>::type;
template <typename T, typename = ValidateType<T>>
static constexpr VariantTypeIndex typeIndexOf();
MVariant();
MVariant(MVariant const& x);
MVariant(MVariant&& x);
template <typename T, typename = ValidateType<T>>
MVariant(T const& x);
template <typename T, typename = ValidateType<T>>
MVariant(T&& x);
MVariant(Variant<Types...> const& x);
MVariant(Variant<Types...>&& x);
~MVariant();
// MVariant::operator= will never invalidate the MVariant, instead it will
// just become empty.
MVariant& operator=(MVariant const& x);
MVariant& operator=(MVariant&& x);
template <typename T, typename = ValidateType<T>>
MVariant& operator=(T const& x);
template <typename T, typename = ValidateType<T>>
MVariant& operator=(T&& x);
MVariant& operator=(Variant<Types...> const& x);
MVariant& operator=(Variant<Types...>&& x);
// Requires that every type included in this MVariant has operator==
bool operator==(MVariant const& x) const;
bool operator!=(MVariant const& x) const;
// Requires that every type included in this MVariant has operator<
bool operator<(MVariant const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator==(T const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator!=(T const& x) const;
template <typename T, typename = ValidateType<T>>
bool operator<(T const& x) const;
// get throws BadVariantCast on bad casts
template <typename T, typename = ValidateType<T>>
T const& get() const;
template <typename T, typename = ValidateType<T>>
T& get();
// maybe() and ptr() do not throw if this MVariant does not hold the given
// type, instead simply returns Nothing / nullptr.
template <typename T, typename = ValidateType<T>>
Maybe<T> maybe() const;
template <typename T, typename = ValidateType<T>>
T const* ptr() const;
template <typename T, typename = ValidateType<T>>
T* ptr();
template <typename T, typename = ValidateType<T>>
bool is() const;
// Takes the given value out and leaves this empty
template <typename T, typename = ValidateType<T>>
T take();
// Returns a Variant of all the allowed types if non-empty, throws
// BadVariantCast if empty.
Variant<Types...> value() const;
// Moves the contents of this MVariant into the given Variant if non-empty,
// throws BadVariantCast if empty.
Variant<Types...> takeValue();
bool empty() const;
void reset();
// Equivalent to !empty()
explicit operator bool() const;
// If this MVariant holds a type, calls the given function with the type
// being held. If nothing is currently held, the function is not called.
template <typename Function>
void call(Function&& function);
template <typename Function>
void call(Function&& function) const;
// Returns an index for the held type, which can be passed into makeType to
// make this MVariant hold a specific type. Types are always indexed in the
// order they are specified starting from 1. A type index of 0 indicates an
// empty MVariant.
VariantTypeIndex typeIndex() const;
// Make this MVariant hold a new default constructed type of the given type
// index. Can only be used if every alternative type has a default
// constructor.
void makeType(VariantTypeIndex typeIndex);
private:
struct MVariantEmpty {
bool operator==(MVariantEmpty const& rhs) const;
bool operator<(MVariantEmpty const& rhs) const;
};
template <typename Function>
struct RefCaller {
Function&& function;
RefCaller(Function&& function);
void operator()(MVariantEmpty& empty);
template <typename T>
void operator()(T& t);
};
template <typename Function>
struct ConstRefCaller {
Function&& function;
ConstRefCaller(Function&& function);
void operator()(MVariantEmpty const& empty);
template <typename T>
void operator()(T const& t);
};
Variant<MVariantEmpty, Types...> m_variant;
};
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
constexpr VariantTypeIndex Variant<FirstType, RestTypes...>::typeIndexOf() {
return TypeIndex<T>::value;
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>::Variant()
: Variant(FirstType()) {}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
Variant<FirstType, RestTypes...>::Variant(T const& x) {
assign(x);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
Variant<FirstType, RestTypes...>::Variant(T&& x) {
assign(std::forward<T>(x));
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>::Variant(Variant const& x) {
x.call([&](auto const& t) {
assign(t);
});
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>::Variant(Variant&& x)
noexcept(detail::IsNothrowMoveConstructible<FirstType, RestTypes...>::value) {
x.call([&](auto& t) {
assign(std::move(t));
});
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>::~Variant() {
destruct();
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>& Variant<FirstType, RestTypes...>::operator=(Variant const& x) {
if (&x == this)
return *this;
x.call([&](auto const& t) {
assign(t);
});
return *this;
}
template <typename FirstType, typename... RestTypes>
Variant<FirstType, RestTypes...>& Variant<FirstType, RestTypes...>::operator=(Variant&& x)
noexcept(detail::IsNothrowMoveAssignable<FirstType, RestTypes...>::value) {
if (&x == this)
return *this;
x.call([&](auto& t) {
assign(std::move(t));
});
return *this;
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
Variant<FirstType, RestTypes...>& Variant<FirstType, RestTypes...>::operator=(T const& x) {
assign(x);
return *this;
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
Variant<FirstType, RestTypes...>& Variant<FirstType, RestTypes...>::operator=(T&& x) {
assign(std::forward<T>(x));
return *this;
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
T const& Variant<FirstType, RestTypes...>::get() const {
if (!is<T>())
throw BadVariantCast();
return *(T*)(&m_buffer);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
T& Variant<FirstType, RestTypes...>::get() {
if (!is<T>())
throw BadVariantCast();
return *(T*)(&m_buffer);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
Maybe<T> Variant<FirstType, RestTypes...>::maybe() const {
if (!is<T>())
return {};
return *(T*)(&m_buffer);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
T const* Variant<FirstType, RestTypes...>::ptr() const {
if (!is<T>())
return nullptr;
return (T*)(&m_buffer);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
T* Variant<FirstType, RestTypes...>::ptr() {
if (!is<T>())
return nullptr;
return (T*)(&m_buffer);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
bool Variant<FirstType, RestTypes...>::is() const {
return m_typeIndex == TypeIndex<T>::value;
}
template <typename FirstType, typename... RestTypes>
template <typename Function>
decltype(auto) Variant<FirstType, RestTypes...>::call(Function&& function) {
return doCall<Function, FirstType, RestTypes...>(std::forward<Function>(function));
}
template <typename FirstType, typename... RestTypes>
template <typename Function>
decltype(auto) Variant<FirstType, RestTypes...>::call(Function&& function) const {
return doCall<Function, FirstType, RestTypes...>(std::forward<Function>(function));
}
template <typename FirstType, typename... RestTypes>
VariantTypeIndex Variant<FirstType, RestTypes...>::typeIndex() const {
return m_typeIndex;
}
template <typename FirstType, typename... RestTypes>
void Variant<FirstType, RestTypes...>::makeType(VariantTypeIndex typeIndex) {
return doMakeType<FirstType, RestTypes...>(typeIndex);
}
template <typename FirstType, typename... RestTypes>
bool Variant<FirstType, RestTypes...>::invalid() const {
return m_typeIndex == InvalidVariantType;
}
template <typename FirstType, typename... RestTypes>
bool Variant<FirstType, RestTypes...>::operator==(Variant const& x) const {
if (this == &x) {
return true;
} else if (typeIndex() != x.typeIndex()) {
return false;
} else {
return call([&x](auto const& t) {
typedef typename std::decay<decltype(t)>::type T;
return t == x.template get<T>();
});
}
}
template <typename FirstType, typename... RestTypes>
bool Variant<FirstType, RestTypes...>::operator!=(Variant const& x) const {
return !operator==(x);
}
template <typename FirstType, typename... RestTypes>
bool Variant<FirstType, RestTypes...>::operator<(Variant const& x) const {
if (this == &x) {
return false;
} else {
auto sti = typeIndex();
auto xti = x.typeIndex();
if (sti != xti) {
return sti < xti;
} else {
return call([&x](auto const& t) {
typedef typename std::decay<decltype(t)>::type T;
return t < x.template get<T>();
});
}
}
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
bool Variant<FirstType, RestTypes...>::operator==(T const& x) const {
if (auto p = ptr<T>())
return *p == x;
return false;
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
bool Variant<FirstType, RestTypes...>::operator!=(T const& x) const {
return !operator==(x);
}
template <typename FirstType, typename... RestTypes>
template <typename T, typename>
bool Variant<FirstType, RestTypes...>::operator<(T const& x) const {
if (auto p = ptr<T>())
return *p == x;
return m_typeIndex < TypeIndex<T>::value;
}
template <typename FirstType, typename... RestTypes>
void Variant<FirstType, RestTypes...>::destruct() {
if (m_typeIndex != InvalidVariantType) {
try {
call([](auto& t) {
typedef typename std::decay<decltype(t)>::type T;
t.~T();
});
m_typeIndex = InvalidVariantType;
} catch (...) {
m_typeIndex = InvalidVariantType;
throw;
}
}
}
template <typename FirstType, typename... RestTypes>
template <typename T>
void Variant<FirstType, RestTypes...>::assign(T&& x) {
typedef typename std::decay<T>::type AssignType;
if (auto p = ptr<AssignType>()) {
*p = std::forward<T>(x);
} else {
destruct();
new (&m_buffer) AssignType(std::forward<T>(x));
m_typeIndex = TypeIndex<AssignType>::value;
}
}
template <typename FirstType, typename... RestTypes>
template <typename Function, typename T>
decltype(auto) Variant<FirstType, RestTypes...>::doCall(Function&& function) {
if (T* p = ptr<T>())
return function(*p);
else
throw BadVariantType();
}
template <typename FirstType, typename... RestTypes>
template <typename Function, typename T1, typename T2, typename... TL>
decltype(auto) Variant<FirstType, RestTypes...>::doCall(Function&& function) {
if (T1* p = ptr<T1>())
return function(*p);
else
return doCall<Function, T2, TL...>(std::forward<Function>(function));
}
template <typename FirstType, typename... RestTypes>
template <typename Function, typename T>
decltype(auto) Variant<FirstType, RestTypes...>::doCall(Function&& function) const {
if (T const* p = ptr<T>())
return function(*p);
else
throw BadVariantType();
}
template <typename FirstType, typename... RestTypes>
template <typename Function, typename T1, typename T2, typename... TL>
decltype(auto) Variant<FirstType, RestTypes...>::doCall(Function&& function) const {
if (T1 const* p = ptr<T1>())
return function(*p);
else
return doCall<Function, T2, TL...>(std::forward<Function>(function));
}
template <typename FirstType, typename... RestTypes>
template <typename First>
void Variant<FirstType, RestTypes...>::doMakeType(VariantTypeIndex typeIndex) {
if (typeIndex == 0)
*this = First();
else
throw BadVariantType();
}
template <typename FirstType, typename... RestTypes>
template <typename First, typename Second, typename... Rest>
void Variant<FirstType, RestTypes...>::doMakeType(VariantTypeIndex typeIndex) {
if (typeIndex == 0)
*this = First();
else
return doMakeType<Second, Rest...>(typeIndex - 1);
}
template <typename... Types>
template <typename T, typename>
constexpr VariantTypeIndex MVariant<Types...>::typeIndexOf() {
return Variant<MVariantEmpty, Types...>::template typeIndexOf<T>();
}
template <typename... Types>
MVariant<Types...>::MVariant() {}
template <typename... Types>
MVariant<Types...>::MVariant(MVariant const& x)
: m_variant(x.m_variant) {}
template <typename... Types>
MVariant<Types...>::MVariant(MVariant&& x) {
m_variant = std::move(x.m_variant);
x.m_variant = MVariantEmpty();
}
template <typename... Types>
MVariant<Types...>::MVariant(Variant<Types...> const& x) {
operator=(x);
}
template <typename... Types>
MVariant<Types...>::MVariant(Variant<Types...>&& x) {
operator=(std::move(x));
}
template <typename... Types>
template <typename T, typename>
MVariant<Types...>::MVariant(T const& x)
: m_variant(x) {}
template <typename... Types>
template <typename T, typename>
MVariant<Types...>::MVariant(T&& x)
: m_variant(std::forward<T>(x)) {}
template <typename... Types>
MVariant<Types...>::~MVariant() {}
template <typename... Types>
MVariant<Types...>& MVariant<Types...>::operator=(MVariant const& x) {
try {
m_variant = x.m_variant;
} catch (...) {
if (m_variant.invalid())
m_variant = MVariantEmpty();
throw;
}
return *this;
}
template <typename... Types>
MVariant<Types...>& MVariant<Types...>::operator=(MVariant&& x) {
try {
m_variant = std::move(x.m_variant);
} catch (...) {
if (m_variant.invalid())
m_variant = MVariantEmpty();
throw;
}
return *this;
}
template <typename... Types>
template <typename T, typename>
MVariant<Types...>& MVariant<Types...>::operator=(T const& x) {
try {
m_variant = x;
} catch (...) {
if (m_variant.invalid())
m_variant = MVariantEmpty();
throw;
}
return *this;
}
template <typename... Types>
template <typename T, typename>
MVariant<Types...>& MVariant<Types...>::operator=(T&& x) {
try {
m_variant = std::forward<T>(x);
} catch (...) {
if (m_variant.invalid())
m_variant = MVariantEmpty();
throw;
}
return *this;
}
template <typename... Types>
MVariant<Types...>& MVariant<Types...>::operator=(Variant<Types...> const& x) {
x.call([this](auto const& t) {
*this = t;
});
return *this;
}
template <typename... Types>
MVariant<Types...>& MVariant<Types...>::operator=(Variant<Types...>&& x) {
x.call([this](auto& t) {
*this = std::move(t);
});
return *this;
}
template <typename... Types>
bool MVariant<Types...>::operator==(MVariant const& x) const {
return m_variant == x.m_variant;
}
template <typename... Types>
bool MVariant<Types...>::operator!=(MVariant const& x) const {
return m_variant != x.m_variant;
}
template <typename... Types>
bool MVariant<Types...>::operator<(MVariant const& x) const {
return m_variant < x.m_variant;
}
template <typename... Types>
template <typename T, typename>
bool MVariant<Types...>::operator==(T const& x) const {
return m_variant == x;
}
template <typename... Types>
template <typename T, typename>
bool MVariant<Types...>::operator!=(T const& x) const {
return m_variant != x;
}
template <typename... Types>
template <typename T, typename>
bool MVariant<Types...>::operator<(T const& x) const {
return m_variant < x;
}
template <typename... Types>
template <typename T, typename>
T const& MVariant<Types...>::get() const {
return m_variant.template get<T>();
}
template <typename... Types>
template <typename T, typename>
T& MVariant<Types...>::get() {
return m_variant.template get<T>();
}
template <typename... Types>
template <typename T, typename>
Maybe<T> MVariant<Types...>::maybe() const {
return m_variant.template maybe<T>();
}
template <typename... Types>
template <typename T, typename>
T const* MVariant<Types...>::ptr() const {
return m_variant.template ptr<T>();
}
template <typename... Types>
template <typename T, typename>
T* MVariant<Types...>::ptr() {
return m_variant.template ptr<T>();
}
template <typename... Types>
template <typename T, typename>
bool MVariant<Types...>::is() const {
return m_variant.template is<T>();
}
template <typename... Types>
template <typename T, typename>
T MVariant<Types...>::take() {
T t = std::move(m_variant.template get<T>());
m_variant = MVariantEmpty();
return t;
}
template <typename... Types>
Variant<Types...> MVariant<Types...>::value() const {
if (empty())
throw BadVariantCast();
Variant<Types...> r;
call([&r](auto const& v) {
r = v;
});
return r;
}
template <typename... Types>
Variant<Types...> MVariant<Types...>::takeValue() {
if (empty())
throw BadVariantCast();
Variant<Types...> r;
call([&r](auto& v) {
r = std::move(v);
});
m_variant = MVariantEmpty();
return r;
}
template <typename... Types>
bool MVariant<Types...>::empty() const {
return m_variant.template is<MVariantEmpty>();
}
template <typename... Types>
void MVariant<Types...>::reset() {
m_variant = MVariantEmpty();
}
template <typename... Types>
MVariant<Types...>::operator bool() const {
return !empty();
}
template <typename... Types>
template <typename Function>
void MVariant<Types...>::call(Function&& function) {
m_variant.call(RefCaller<Function>(std::forward<Function>(function)));
}
template <typename... Types>
template <typename Function>
void MVariant<Types...>::call(Function&& function) const {
m_variant.call(ConstRefCaller<Function>(std::forward<Function>(function)));
}
template <typename... Types>
VariantTypeIndex MVariant<Types...>::typeIndex() const {
return m_variant.typeIndex();
}
template <typename... Types>
void MVariant<Types...>::makeType(VariantTypeIndex typeIndex) {
m_variant.makeType(typeIndex);
}
template <typename... Types>
bool MVariant<Types...>::MVariantEmpty::operator==(MVariantEmpty const&) const {
return true;
}
template <typename... Types>
bool MVariant<Types...>::MVariantEmpty::operator<(MVariantEmpty const&) const {
return false;
}
template <typename... Types>
template <typename Function>
MVariant<Types...>::RefCaller<Function>::RefCaller(Function&& function)
: function(std::forward<Function>(function)) {}
template <typename... Types>
template <typename Function>
void MVariant<Types...>::RefCaller<Function>::operator()(MVariantEmpty&) {}
template <typename... Types>
template <typename Function>
template <typename T>
void MVariant<Types...>::RefCaller<Function>::operator()(T& t) {
function(t);
}
template <typename... Types>
template <typename Function>
MVariant<Types...>::ConstRefCaller<Function>::ConstRefCaller(Function&& function)
: function(std::forward<Function>(function)) {}
template <typename... Types>
template <typename Function>
void MVariant<Types...>::ConstRefCaller<Function>::operator()(MVariantEmpty const&) {}
template <typename... Types>
template <typename Function>
template <typename T>
void MVariant<Types...>::ConstRefCaller<Function>::operator()(T const& t) {
function(t);
}
}
template <typename FirstType, typename... RestTypes>
struct fmt::formatter<Star::Variant<FirstType, RestTypes...>> : ostream_formatter {};
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