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Compilation fixes

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This commit is contained in:
Simon Brand
2017-10-01 14:54:19 +01:00
parent 3c0369cc83
commit 94e83f04e1
1 changed files with 219 additions and 64 deletions
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283
optional.hpp
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@@ -11,24 +11,97 @@
/// ///
#include <type_traits> #include <type_traits>
#include "tl/type_traits.hpp" #include <utility>
#include <exception>
#include <new>
namespace tl { namespace tl {
template <class T> using remove_cv_t = typename std::remove_cv<T>::type;
template <class T> using remove_const_t = typename std::remove_const<T>::type;
template <class T> using remove_volatile_t = typename std::remove_volatile<T>::type;
template <class T> using add_cv_t = typename std::add_cv<T>::type;
template <class T> using add_const_t = typename std::add_const<T>::type;
template <class T> using add_volatile_t = typename std::add_volatile<T>::type;
template <class T> using remove_reference_t = typename std::remove_reference<T>::type;
template <class T> using add_lvalue_reference_t = typename std::add_lvalue_reference<T>::type;
template <class T> using add_rvalue_reference_t = typename std::add_rvalue_reference<T>::type;
template <class T> using remove_pointer_t = typename std::remove_pointer<T>::type;
template <class T> using add_pointer_t = typename std::add_pointer<T>::type;
template <class T> using make_signed_t = typename std::make_signed<T>::type;
template <class T> using make_unsigned_t = typename std::make_unsigned<T>::type;
template <class T> using remove_extent_t = typename std::remove_extent<T>::type;
template <class T> using remove_all_extents_t = typename std::remove_all_extents<T>::type;
template <std::size_t N, std::size_t A=N> using aligned_storage_t = typename std::aligned_storage<N,A>::type;
template <std::size_t N, class... Ts> using aligned_union_t = typename std::aligned_union<N,Ts...>::type;
template <class T> using decay_t = typename std::decay<T>::type;
template <bool E, class T=void> using enable_if_t = typename std::enable_if<E,T>::type;
template <bool B, class T, class F> using conditional_t = typename std::conditional<B,T,F>::type;
template <class... Ts> using common_type_t = typename std::common_type<Ts...>::type;
template <class T> using underlying_type_t = typename std::underlying_type<T>::type;
template <class T> using result_of_t = typename std::result_of<T>::type;
template<class...> struct voider { using type = void; };
template<class...Ts> using void_t = typename voider<Ts...>::type;
struct in_place_t {
explicit in_place_t() = default;
};
static constexpr in_place_t in_place{};
// [optional.optional], class template optional // [optional.optional], class template optional
template <class T> template <class T>
class optional; class optional;
namespace detail {
template <class T, class U>
using enable_forward_value = tl::enable_if_t<
std::is_constructible<T, U&&>::value &&
!std::is_same<tl::decay_t<U>, in_place_t>::value &&
!std::is_same<optional<T>, tl::decay_t<U>>::value
>;
template <class T, class U, class Other>
using enable_from_other = tl::enable_if_t<
std::is_constructible<T, Other>::value &&
!std::is_constructible<T, optional<U>&>::value &&
!std::is_constructible<T, optional<U>&&>::value &&
!std::is_constructible<T, const optional<U>&>::value &&
!std::is_constructible<T, const optional<U>&&>::value &&
!std::is_convertible<optional<U>&, T>::value &&
!std::is_convertible<optional<U>&&, T>::value &&
!std::is_convertible<const optional<U>&, T>::value &&
!std::is_convertible<const optional<U>&&, T>::value
>;
}
//TODO improve
template <class T, class=void>
struct is_swappable : std::false_type{};
template <class T>
struct is_swappable<T,void_t<decltype(swap(std::declval<T>(), std::declval<T>()))>>
: std::true_type{};
//TODO improve
template <class T, class=void>
struct is_nothrow_swappable : std::false_type{};
template <class T>
struct is_nothrow_swappable<T,void_t<decltype(swap(std::declval<T>(), std::declval<T>()))>>
: std::true_type{};
// [optional.nullopt], no-value state indicator // [optional.nullopt], no-value state indicator
struct nullopt_t{ struct nullopt_t{
struct do_not_use{}; struct do_not_use{};
constexpr explicit nullopt(do_not_use, do_not_use) noexcept{} constexpr explicit nullopt_t(do_not_use, do_not_use) noexcept{}
}; };
inline constexpr nullopt_t nullopt{nullopt_t::do_not_use{}, nullopt_t::do_not_use{}}; static constexpr nullopt_t nullopt{nullopt_t::do_not_use{}, nullopt_t::do_not_use{}};
// [optional.bad.access], class bad_­optional_­access // [optional.bad.access], class bad_optional_access
class bad_optional_access : public std::exception { class bad_optional_access : public std::exception {
public:
bad_optional_access() = default; bad_optional_access() = default;
const char* what() const { const char* what() const noexcept {
return "Optional has no value"; return "Optional has no value";
} }
}; };
@@ -79,7 +152,6 @@ namespace tl {
return lhs.value() <= rhs.value(); return lhs.value() <= rhs.value();
} }
}
template <class T, class U> template <class T, class U>
inline constexpr bool operator>=(const optional<T>& lhs, const optional<U>& rhs) { inline constexpr bool operator>=(const optional<T>& lhs, const optional<U>& rhs) {
if (!rhs.has_value()) if (!rhs.has_value())
@@ -168,30 +240,31 @@ template <class T, class U> inline constexpr bool operator>=(const U& lhs, const
// [optional.specalg], specialized algorithms // [optional.specalg], specialized algorithms
template <class T, tl::enable_if_t<std::is_move_constructible<T>::value* = nullptr, template <class T, tl::enable_if_t<std::is_move_constructible<T>::value>* = nullptr,
tl:enable_if_t<std::is_swappable_v<T>>* = nullptr> tl::enable_if_t<is_swappable<T>::value>* = nullptr>
void swap(optional<T>& lhs, optional<T>& rhs) noexcept(noexcept(lhs.swap(rhs))) { void swap(optional<T>& lhs, optional<T>& rhs) noexcept(noexcept(lhs.swap(rhs))) {
return lhs.swap(rhs); return lhs.swap(rhs);
} }
template <class T> template <class T>
inline constexpr optional<tl::decay_t<T>> make_optional(T&& v) { inline constexpr optional<tl::decay_t<T>> make_optional(T&& v) {
return optional<decay_t<T>>(std​::​forward<T>(v)); return optional<decay_t<T>>(std::forward<T>(v));
} }
template <class T, class... Args> template <class T, class... Args>
inline constexpr optional<T> make_optional(Args&&... args) { inline constexpr optional<T> make_optional(Args&&... args) {
return optional<T>(in_place, std​::​forward<Args>(args)...); return optional<T>(in_place, std::forward<Args>(args)...);
} }
template <class T, class U, class... Args> template <class T, class U, class... Args>
inline constexpr optional<T> make_optional(initializer_list<U> il, Args&&... args) { inline constexpr optional<T> make_optional(std::initializer_list<U> il, Args&&... args) {
return optional<T>(in_place, il, std​::​forward<Args>(args)...); return optional<T>(in_place, il, std::forward<Args>(args)...);
} }
} }
// [optional.hash], hash support // [optional.hash], hash support
namespace std { namespace std {
template <class T> struct hash; template <class T> struct hash;
template <class T, class = decltype(hash<tl::remove_const_t<T>>{})> //TODO SFINAE
template <class T>
struct hash<tl::optional<T>> { struct hash<tl::optional<T>> {
std::size_t operator() (const tl::optional<T>& o) { std::size_t operator() (const tl::optional<T>& o) {
if (!o.has_value()) if (!o.has_value())
@@ -199,143 +272,225 @@ namespace std {
return hash<tl::remove_const_t<T>>()(o.value()); return hash<tl::remove_const_t<T>>()(o.value());
} }
} };
} }
namespace tl { namespace tl {
namespace detail { namespace detail {
template <class T> template <class T, bool = std::is_trivially_destructible<T>::value>
struct optional_base : <T> { struct optional_storage_base {
~optional_storage_base() {
if (m_has_value) {
m_value.~T();
m_has_value = false;
}
}
struct dummy{};
union {
dummy m_dummy;
T m_value;
};
bool m_has_value = false;
};
template <class T>
struct optional_storage_base<T, true> {
~optional_storage_base() {
if (m_has_value) {
//don't destruct value
m_has_value = false;
}
}
struct dummy{};
union {
dummy m_dummy;
T m_value;
};
bool m_has_value = false;
}; };
} }
template <class T> template <class T>
class optional : private detail::optional_base<T> { class optional : private detail::optional_storage_base<T> {
public: public:
using value_type = T; using value_type = T;
// [optional.ctor], constructors // [optional.ctor], constructors
constexpr optional() noexcept = default; constexpr optional() noexcept = default;
constexpr optional(nullopt_t) noexcept = default; constexpr optional(nullopt_t) noexcept {};
constexpr optional(const optional& rhs) = default; constexpr optional(const optional& rhs) {
constexpr optional(optional&&); if (rhs.has_value()) {
template <class... Args> this->m_has_value = true;
constexpr explicit optional(in_place_t, Args&&...); new (std::addressof(this->m_value)) T (rhs.value());
template <class U, class... Args> }
constexpr explicit optional(in_place_t, initializer_list<U>, Args&&...); }
template <class U = T> template <class U = T, tl::enable_if_t<std::is_move_constructible<T>::value>* = nullptr>
EXPLICIT constexpr optional(U&&); constexpr optional(optional&& rhs) {
template <class U> if (rhs.has_value()) {
EXPLICIT optional(const optional<U>&); this->m_has_value = true;
template <class U> new (std::addressof(this->m_value)) T (std::move(rhs.value()));
EXPLICIT optional(optional<U>&&); }
}
template <class... Args>
constexpr explicit optional(tl::enable_if_t<std::is_constructible<T, Args...>::value, in_place_t>,
Args&&... args) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (std::forward<Args>(args)...);
}
template <class U, class... Args>
constexpr explicit optional(
tl::enable_if_t<std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value, in_place_t>,
std::initializer_list<U> il, Args&&... args) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (il, std::forward<Args>(args)...);
}
template <class U = T, tl::enable_if_t<std::is_convertible<U&&, T>::value>* = nullptr,
detail::enable_forward_value<T,U>* = nullptr>
constexpr optional(U&& u) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (std::forward<U>(u));
}
template <class U = T, tl::enable_if_t<!std::is_convertible<U&&, T>::value>* = nullptr,
detail::enable_forward_value<T,U>* = nullptr>
constexpr explicit optional(U&& u) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (std::forward<U>(u));
}
template <class U, detail::enable_from_other<T,U,const U&>* = nullptr,
tl::enable_if_t<std::is_convertible<const U&, T>::value>* = nullptr>
optional(const optional<U>& rhs) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (rhs.value());
}
template <class U, detail::enable_from_other<T,U,const U&>* = nullptr,
tl::enable_if_t<!std::is_convertible<const U&, T>::value>* = nullptr>
optional(const optional<U>& rhs) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (rhs.value());
}
template <class U, detail::enable_from_other<T,U,U&&>* = nullptr,
tl::enable_if_t<std::is_convertible<U&&, T>::value>* = nullptr>
optional(optional<U>&& rhs) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (std::move(rhs.value()));
}
template <class U, detail::enable_from_other<T,U,U&&>* = nullptr,
enable_if_t<!std::is_convertible<U&&, T>::value>* = nullptr>
explicit optional(optional<U>&& rhs) {
this->m_has_value = true;
new (std::addressof(this->m_value)) T (std::move(rhs.value()));
}
// [optional.dtor], destructor // [optional.dtor], destructor
~optional(); ~optional() = default;
// [optional.assign], assignment // [optional.assign], assignment
optional& operator=(nullopt_t) noexcept; optional& operator=(nullopt_t) noexcept;
optional& operator=(const optional&); optional& operator=(const optional&);
optional& operator=(optional&&) noexcept(see below); optional& operator=(optional&&) noexcept;
template <class U = T> optional& operator=(U&&); template <class U = T> optional& operator=(U&&);
template <class U> optional& operator=(const optional<U>&); template <class U> optional& operator=(const optional<U>&);
template <class U> optional& operator=(optional<U>&&); template <class U> optional& operator=(optional<U>&&);
template <class... Args> T& emplace(Args&&...) { template <class... Args> T& emplace(Args&&... args) {
static_assert(std::is_constructible<T, Args&&...>::value, static_assert(std::is_constructible<T, Args&&...>::value,
"T must be constructible with Args"); "T must be constructible with Args");
*this = nullopt; *this = nullopt;
new (std::addressof(m_storage.t)) T(std​::​forward<Args>(args)...); new (std::addressof(this->m_value)) T(std::forward<Args>(args)...);
} }
template <class U, class... Args> template <class U, class... Args>
tl::enable_if_t<std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value, T&> tl::enable_if_t<std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value, T&>
T& emplace(initializer_list<U>, Args&&...) { emplace(std::initializer_list<U> il, Args&&... args) {
*this = nullopt; *this = nullopt;
new (std::addressof(m_storage.t)) T(il, std​::​forward<Args>(args)...); new (std::addressof(this->m_value)) T(il, std::forward<Args>(args)...);
} }
// [optional.swap], swap // [optional.swap], swap
void swap(optional& rhs) void swap(optional& rhs)
noexcept(std::is_nothrow_move_constructible_v<T>::value && std::is_nothrow_swappable<T>::value) noexcept(std::is_nothrow_move_constructible<T>::value && is_nothrow_swappable<T>::value)
{ {
if (lhs.has_value()) { if (has_value()) {
if (rhs.has_value()) { if (rhs.has_value()) {
using std::swap; using std::swap;
swap(value(), rhs.value()); swap(value(), rhs.value());
} }
else { else {
new (&rhs.m_storage.t) T (std::move(m_storage.t)); new (&rhs.m_value) T (std::move(this->m_value));
m_storage.t.T::~T(); this->m_value.T::~T();
} }
} }
else if (rhs.has_value()) { else if (rhs.has_value()) {
new (std::addressof(m_storage.t)) T (std::move(rhs.m_storage.t)); new (std::addressof(this->m_value)) T (std::move(rhs.m_value));
rhs.m_storage.t.T::~T(); rhs.m_value.T::~T();
} }
} }
// [optional.observe], observers // [optional.observe], observers
constexpr const T* operator->() const { constexpr const T* operator->() const {
return std::addressof(m_storage.t); return std::addressof(this->m_value);
} }
constexpr T* operator->() { constexpr T* operator->() {
return std::addressof(m_storage.t); return std::addressof(this->m_value);
} }
constexpr const T& operator*() const& { constexpr const T& operator*() const& {
return m_storage.t; return this->m_value;
} }
constexpr T& operator*() & { constexpr T& operator*() & {
return m_storage.t; return this->m_value;
} }
constexpr T&& operator*() && { constexpr T&& operator*() && {
return std::move(m_storage.t); return std::move(this->m_value);
} }
constexpr const T&& operator*() const&& { constexpr const T&& operator*() const&& {
return std::move(m_storage.t); return std::move(this->m_value);
} }
constexpr explicit operator bool() const noexcept { constexpr explicit operator bool() const noexcept {
return m_has_value; return this->m_has_value;
} }
constexpr bool has_value() const noexcept { constexpr bool has_value() const noexcept {
return m_has_value; return this->m_has_value;
} }
constexpr const T& value() const& { constexpr const T& value() const& {
return has_value() ? m_storage.t : throw bad_optional_access(); return has_value() ? this->m_value : throw bad_optional_access();
} }
constexpr T& value() & { constexpr T& value() & {
return has_value() ? m_storage.t : throw bad_optional_access(); return has_value() ? this->m_value : throw bad_optional_access();
} }
constexpr T&& value() && { constexpr T&& value() && {
return has_value() ? std::move(m_storage.t) : throw bad_optional_access(); return has_value() ? std::move(this->m_value) : throw bad_optional_access();
} }
constexpr const T&& value() const&& { constexpr const T&& value() const&& {
return has_value() ? std::move(m_storage.t) : throw bad_optional_access(); return has_value() ? std::move(this->m_value) : throw bad_optional_access();
} }
template <class U> constexpr T value_or(U&&) const& { template <class U> constexpr T value_or(U&& u) const& {
static_assert(std::is_copy_constructible<T>::value && std::is_convertible<U&&, T>::value, static_assert(std::is_copy_constructible<T>::value && std::is_convertible<U&&, T>::value,
"T must be copy constructible and convertible from U"); "T must be copy constructible and convertible from U");
return has_value() ? value() : static_cast<T>(std::forward<U>(v)); return has_value() ? value() : static_cast<T>(std::forward<U>(u));
} }
template <class U> constexpr T value_or(U&&) && { template <class U> constexpr T value_or(U&& u) && {
static_assert(std::is_move_constructible<T>::value && std::is_convertible<U&&, T>::value, static_assert(std::is_move_constructible<T>::value && std::is_convertible<U&&, T>::value,
"T must be move constructible and convertible from U"); "T must be move constructible and convertible from U");
return has_value() ? value() : static_cast<T>(std::forward<U>(v)); return has_value() ? value() : static_cast<T>(std::forward<U>(u));
} }
// [optional.mod], modifiers // [optional.mod], modifiers
void reset() noexcept; void reset() noexcept;
private: private:
struct dummy{};
union {
dummy d;
T t;
} m_storage;
bool m_has_value;
}; };
} }