| /* |
| * Copyright (C) 2016-2017 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| // Implementation of Library Fundamentals v3's std::expected, as described here: http://wg21.link/p0323r4 |
| |
| #pragma once |
| |
| /* |
| expected synopsis |
| |
| namespace std { |
| namespace experimental { |
| inline namespace fundamentals_v3 { |
| // ?.?.4, Expected for object types |
| template <class T, class E> |
| class expected; |
| |
| // ?.?.5, Expected specialization for void |
| template <class E> |
| class expected<void,E>; |
| |
| // ?.?.6, unexpect tag |
| struct unexpect_t { |
| unexpect_t() = default; |
| }; |
| inline constexpr unexpect_t unexpect{}; |
| |
| // ?.?.7, class bad_expected_access |
| template <class E> |
| class bad_expected_access; |
| |
| // ?.?.8, Specialization for void. |
| template <> |
| class bad_expected_access<void>; |
| |
| // ?.?.9, Expected relational operators |
| template <class T, class E> |
| constexpr bool operator==(const expected<T, E>&, const expected<T, E>&); |
| template <class T, class E> |
| constexpr bool operator!=(const expected<T, E>&, const expected<T, E>&); |
| |
| // ?.?.10, Comparison with T |
| template <class T, class E> |
| constexpr bool operator==(const expected<T, E>&, const T&); |
| template <class T, class E> |
| constexpr bool operator==(const T&, const expected<T, E>&); |
| template <class T, class E> |
| constexpr bool operator!=(const expected<T, E>&, const T&); |
| template <class T, class E> |
| constexpr bool operator!=(const T&, const expected<T, E>&); |
| |
| // ?.?.10, Comparison with unexpected<E> |
| template <class T, class E> |
| constexpr bool operator==(const expected<T, E>&, const unexpected<E>&); |
| template <class T, class E> |
| constexpr bool operator==(const unexpected<E>&, const expected<T, E>&); |
| template <class T, class E> |
| constexpr bool operator!=(const expected<T, E>&, const unexpected<E>&); |
| template <class T, class E> |
| constexpr bool operator!=(const unexpected<E>&, const expected<T, E>&); |
| |
| // ?.?.11, Specialized algorithms |
| void swap(expected<T, E>&, expected<T, E>&) noexcept(see below); |
| |
| template <class T, class E> |
| class expected |
| { |
| public: |
| typedef T value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| |
| template <class U> |
| struct rebind { |
| using type = expected<U, error_type>; |
| }; |
| |
| // ?.?.4.1, constructors |
| constexpr expected(); |
| constexpr expected(const expected&); |
| constexpr expected(expected&&) noexcept(see below); |
| template <class U, class G> |
| EXPLICIT constexpr expected(const expected<U, G>&); |
| template <class U, class G> |
| EXPLICIT constexpr expected(expected<U, G>&&); |
| |
| template <class U = T> |
| EXPLICIT constexpr expected(U&& v); |
| |
| template <class... Args> |
| constexpr explicit expected(in_place_t, Args&&...); |
| template <class U, class... Args> |
| constexpr explicit expected(in_place_t, initializer_list<U>, Args&&...); |
| template <class G = E> |
| constexpr expected(unexpected<G> const&); |
| template <class G = E> |
| constexpr expected(unexpected<G> &&); |
| template <class... Args> |
| constexpr explicit expected(unexpect_t, Args&&...); |
| template <class U, class... Args> |
| constexpr explicit expected(unexpect_t, initializer_list<U>, Args&&...); |
| |
| // ?.?.4.2, destructor |
| ~expected(); |
| |
| // ?.?.4.3, assignment |
| expected& operator=(const expected&); |
| expected& operator=(expected&&) noexcept(see below); |
| template <class U = T> expected& operator=(U&&); |
| template <class G = E> |
| expected& operator=(const unexpected<G>&); |
| template <class G = E> |
| expected& operator=(unexpected<G>&&) noexcept(see below); |
| |
| template <class... Args> |
| void emplace(Args&&...); |
| template <class U, class... Args> |
| void emplace(initializer_list<U>, Args&&...); |
| |
| // ?.?.4.4, swap |
| void swap(expected&) noexcept(see below); |
| |
| // ?.?.4.5, observers |
| constexpr const T* operator ->() const; |
| constexpr T* operator ->(); |
| constexpr const T& operator *() const&; |
| constexpr T& operator *() &; |
| constexpr const T&& operator *() const &&; |
| constexpr T&& operator *() &&; |
| constexpr explicit operator bool() const noexcept; |
| constexpr bool has_value() const noexcept; |
| constexpr const T& value() const&; |
| constexpr T& value() &; |
| constexpr const T&& value() const &&; |
| constexpr T&& value() &&; |
| constexpr const E& error() const&; |
| constexpr E& error() &; |
| constexpr const E&& error() const &&; |
| constexpr E&& error() &&; |
| template <class U> |
| constexpr T value_or(U&&) const&; |
| template <class U> |
| T value_or(U&&) &&; |
| |
| private: |
| bool has_val; // exposition only |
| union |
| { |
| value_type val; // exposition only |
| unexpected_type unexpect; // exposition only |
| }; |
| }; |
| |
| }}} |
| |
| */ |
| |
| #include <cstdlib> |
| #include <initializer_list> |
| #include <type_traits> |
| #include <utility> |
| #include <wtf/Assertions.h> |
| #include <wtf/Compiler.h> |
| #include <wtf/StdLibExtras.h> |
| #include <wtf/Unexpected.h> |
| |
| namespace std { |
| namespace experimental { |
| inline namespace fundamentals_v3 { |
| |
| struct unexpected_t { |
| unexpected_t() = default; |
| }; |
| #if __cplusplus < 201703L |
| #define __EXPECTED_INLINE_VARIABLE static const |
| #else |
| #define __EXPECTED_INLINE_VARIABLE inline |
| #endif |
| |
| __EXPECTED_INLINE_VARIABLE constexpr unexpected_t unexpect { }; |
| |
| template<class E> class bad_expected_access; |
| |
| template<> |
| class bad_expected_access<void> : public std::exception { |
| public: |
| explicit bad_expected_access() { } |
| }; |
| |
| template<class E> |
| class bad_expected_access : public bad_expected_access<void> { |
| public: |
| explicit bad_expected_access(E val) : val(val) { } |
| virtual const char* what() const noexcept override { return std::exception::what(); } |
| E& error() & { return val; } |
| const E& error() const& { return val; } |
| E&& error() && { return std::move(val); } |
| const E&& error() const&& { return std::move(val); } |
| |
| private: |
| E val; |
| }; |
| |
| namespace __expected_detail { |
| |
| #if COMPILER_SUPPORTS(EXCEPTIONS) |
| #define __EXPECTED_THROW(__exception) (throw __exception) |
| #else |
| inline NO_RETURN_DUE_TO_CRASH void __expected_terminate() { RELEASE_ASSERT_NOT_REACHED(); } |
| #define __EXPECTED_THROW(...) __expected_detail::__expected_terminate() |
| #endif |
| |
| __EXPECTED_INLINE_VARIABLE constexpr enum class value_tag_t { } value_tag { }; |
| __EXPECTED_INLINE_VARIABLE constexpr enum class error_tag_t { } error_tag { }; |
| |
| template<class T, std::enable_if_t<std::is_trivially_destructible<T>::value>* = nullptr> void destroy(T&) { } |
| template<class T, std::enable_if_t<!std::is_trivially_destructible<T>::value && (std::is_class<T>::value || std::is_union<T>::value)>* = nullptr> void destroy(T& t) { t.~T(); } |
| |
| template<class T, class E> |
| union constexpr_storage { |
| typedef T value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| char dummy; |
| value_type val; |
| error_type err; |
| constexpr constexpr_storage() : dummy() { } |
| constexpr constexpr_storage(value_tag_t) : val() { } |
| constexpr constexpr_storage(error_tag_t) : err() { } |
| template<typename U = T> |
| constexpr constexpr_storage(value_tag_t, U&& v) : val(std::forward<U>(v)) { } |
| template<typename U = E> |
| constexpr constexpr_storage(error_tag_t, U&& e) : err(std::forward<U>(e)) { } |
| ~constexpr_storage() = default; |
| }; |
| |
| template<class T, class E> |
| union storage { |
| typedef T value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| char dummy; |
| value_type val; |
| error_type err; |
| constexpr storage() : dummy() { } |
| constexpr storage(value_tag_t) : val() { } |
| constexpr storage(error_tag_t) : err() { } |
| constexpr storage(value_tag_t, const value_type& val) : val(val) { } |
| constexpr storage(value_tag_t, value_type&& val) : val(std::forward<value_type>(val)) { } |
| constexpr storage(error_tag_t, const error_type& err) : err(err) { } |
| constexpr storage(error_tag_t, error_type&& err) : err(std::forward<error_type>(err)) { } |
| ~storage() { } |
| }; |
| |
| template<class E> |
| union constexpr_storage<void, E> { |
| typedef void value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| char dummy; |
| error_type err; |
| constexpr constexpr_storage() : dummy() { } |
| constexpr constexpr_storage(value_tag_t) : dummy() { } |
| constexpr constexpr_storage(error_tag_t) : err() { } |
| constexpr constexpr_storage(error_tag_t, const error_type& e) : err(e) { } |
| ~constexpr_storage() = default; |
| }; |
| |
| template<class E> |
| union storage<void, E> { |
| typedef void value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| char dummy; |
| error_type err; |
| constexpr storage() : dummy() { } |
| constexpr storage(value_tag_t) : dummy() { } |
| constexpr storage(error_tag_t) : err() { } |
| constexpr storage(error_tag_t, const error_type& err) : err(err) { } |
| constexpr storage(error_tag_t, error_type&& err) : err(std::forward<error_type>(err)) { } |
| ~storage() { } |
| }; |
| |
| template<class T, class E> |
| struct constexpr_base { |
| typedef T value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| constexpr_storage<value_type, error_type> s; |
| bool has; |
| constexpr constexpr_base() : s(), has(true) { } |
| constexpr constexpr_base(value_tag_t tag) : s(tag), has(true) { } |
| constexpr constexpr_base(error_tag_t tag) : s(tag), has(false) { } |
| template<typename U = T> |
| constexpr constexpr_base(value_tag_t tag, U&& val) : s(tag, std::forward<U>(val)), has(true) { } |
| template<typename U = E> |
| constexpr constexpr_base(error_tag_t tag, U&& err) : s(tag, std::forward<U>(err)), has(false) { } |
| ~constexpr_base() = default; |
| }; |
| |
| template<class T, class E> |
| struct base { |
| typedef T value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| storage<value_type, error_type> s; |
| bool has; |
| constexpr base() : s(), has(true) { } |
| constexpr base(value_tag_t tag) : s(tag), has(true) { } |
| constexpr base(error_tag_t tag) : s(tag), has(false) { } |
| constexpr base(value_tag_t tag, const value_type& val) : s(tag, val), has(true) { } |
| constexpr base(value_tag_t tag, value_type&& val) : s(tag, std::forward<value_type>(val)), has(true) { } |
| constexpr base(error_tag_t tag, const error_type& err) : s(tag, err), has(false) { } |
| constexpr base(error_tag_t tag, error_type&& err) : s(tag, std::forward<error_type>(err)), has(false) { } |
| base(const base& o) |
| : has(o.has) |
| { |
| if (has) |
| ::new (std::addressof(s.val)) value_type(o.s.val); |
| else |
| ::new (std::addressof(s.err)) error_type(o.s.err); |
| } |
| base(base&& o) |
| : has(o.has) |
| { |
| if (has) |
| ::new (std::addressof(s.val)) value_type(std::move(o.s.val)); |
| else |
| ::new (std::addressof(s.err)) error_type(std::move(o.s.err)); |
| } |
| ~base() |
| { |
| if (has) |
| destroy(s.val); |
| else |
| destroy(s.err); |
| } |
| }; |
| |
| template<class E> |
| struct constexpr_base<void, E> { |
| typedef void value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| constexpr_storage<value_type, error_type> s; |
| bool has; |
| constexpr constexpr_base() : s(), has(true) { } |
| constexpr constexpr_base(value_tag_t tag) : s(tag), has(true) { } |
| constexpr constexpr_base(error_tag_t tag) : s(tag), has(false) { } |
| constexpr constexpr_base(error_tag_t tag, const error_type& err) : s(tag, err), has(false) { } |
| constexpr constexpr_base(error_tag_t tag, error_type&& err) : s(tag, std::forward<error_type>(err)), has(false) { } |
| ~constexpr_base() = default; |
| }; |
| |
| template<class E> |
| struct base<void, E> { |
| typedef void value_type; |
| typedef E error_type; |
| typedef unexpected<E> unexpected_type; |
| storage<value_type, error_type> s; |
| bool has; |
| constexpr base() : s(), has(true) { } |
| constexpr base(value_tag_t tag) : s(tag), has(true) { } |
| constexpr base(error_tag_t tag) : s(tag), has(false) { } |
| constexpr base(error_tag_t tag, const error_type& err) : s(tag, err), has(false) { } |
| constexpr base(error_tag_t tag, error_type&& err) : s(tag, std::forward<error_type>(err)), has(false) { } |
| base(const base& o) |
| : has(o.has) |
| { |
| if (!has) |
| ::new (std::addressof(s.err)) error_type(o.s.err); |
| } |
| base(base&& o) |
| : has(o.has) |
| { |
| if (!has) |
| ::new (std::addressof(s.err)) error_type(std::move(o.s.err)); |
| } |
| ~base() |
| { |
| if (!has) |
| destroy(s.err); |
| } |
| }; |
| |
| template<class T, class E> |
| using base_select = typename std::conditional< |
| ((std::is_void<T>::value || std::is_trivially_destructible<T>::value) |
| && std::is_trivially_destructible<E>::value), |
| constexpr_base<typename std::remove_const<T>::type, typename std::remove_const<E>::type>, |
| base<typename std::remove_const<T>::type, typename std::remove_const<E>::type> |
| >::type; |
| |
| } // namespace __expected_detail |
| |
| template<class T, class E> |
| class expected : private __expected_detail::base_select<T, E> { |
| typedef __expected_detail::base_select<T, E> base; |
| |
| public: |
| typedef typename base::value_type value_type; |
| typedef typename base::error_type error_type; |
| typedef typename base::unexpected_type unexpected_type; |
| |
| private: |
| typedef expected<value_type, error_type> type; |
| |
| public: |
| template<class U> struct rebind { |
| using type = expected<U, error_type>; |
| }; |
| |
| constexpr expected() : base(__expected_detail::value_tag) { } |
| expected(const expected&) = default; |
| expected(expected&&) = default; |
| |
| constexpr expected(const value_type& e) : base(__expected_detail::value_tag, e) { } |
| constexpr expected(value_type&& e) : base(__expected_detail::value_tag, std::forward<value_type>(e)) { } |
| template<class... Args> constexpr explicit expected(std::in_place_t, Args&&... args) : base(__expected_detail::value_tag, value_type(std::forward<Args>(args)...)) { } |
| // template<class U, class... Args> constexpr explicit expected(in_place_t, std::initializer_list<U>, Args&&...); |
| constexpr expected(const unexpected_type& u) : base(__expected_detail::error_tag, u.value()) { } |
| constexpr expected(unexpected_type&& u) : base(__expected_detail::error_tag, std::forward<unexpected_type>(u).value()) { } |
| template<class Err> constexpr expected(const unexpected<Err>& u) : base(__expected_detail::error_tag, u.value()) { } |
| template<class Err> constexpr expected(unexpected<Err>&& u) : base(__expected_detail::error_tag, std::forward<Err>(u.value())) { } |
| template<class... Args> constexpr explicit expected(unexpected_t, Args&&... args) : base(__expected_detail::value_tag, unexpected_type(std::forward<Args>(args)...)) { } |
| // template<class U, class... Args> constexpr explicit expected(unexpected_t, std::initializer_list<U>, Args&&...); |
| |
| ~expected() = default; |
| |
| expected& operator=(const expected& e) { type(e).swap(*this); return *this; } |
| expected& operator=(expected&& e) { type(std::move(e)).swap(*this); return *this; } |
| template<class U> expected& operator=(U&& u) { type(std::move(u)).swap(*this); return *this; } |
| expected& operator=(const unexpected_type& u) { type(u).swap(*this); return *this; } |
| expected& operator=(unexpected_type&& u) { type(std::move(u)).swap(*this); return *this; } |
| // template<class... Args> void emplace(Args&&...); |
| // template<class U, class... Args> void emplace(std::initializer_list<U>, Args&&...); |
| |
| void swap(expected& o) |
| { |
| using std::swap; |
| if (base::has && o.has) |
| swap(base::s.val, o.s.val); |
| else if (base::has && !o.has) { |
| error_type e(std::move(o.s.err)); |
| __expected_detail::destroy(o.s.err); |
| ::new (std::addressof(o.s.val)) value_type(std::move(base::s.val)); |
| __expected_detail::destroy(base::s.val); |
| ::new (std::addressof(base::s.err)) error_type(std::move(e)); |
| swap(base::has, o.has); |
| } else if (!base::has && o.has) { |
| value_type v(std::move(o.s.val)); |
| __expected_detail::destroy(o.s.val); |
| ::new (std::addressof(o.s.err)) error_type(std::move(base::s.err)); |
| __expected_detail::destroy(base::s.err); |
| ::new (std::addressof(base::s.val)) value_type(std::move(v)); |
| swap(base::has, o.has); |
| } else |
| swap(base::s.err, o.s.err); |
| } |
| |
| constexpr const value_type* operator->() const { return &base::s.val; } |
| value_type* operator->() { return &base::s.val; } |
| constexpr const value_type& operator*() const & { return base::s.val; } |
| value_type& operator*() & { return base::s.val; } |
| constexpr const value_type&& operator*() const && { return std::move(base::s.val); } |
| constexpr value_type&& operator*() && { return std::move(base::s.val); } |
| constexpr explicit operator bool() const { return base::has; } |
| constexpr bool has_value() const { return base::has; } |
| constexpr const value_type& value() const & { return base::has ? base::s.val : (__EXPECTED_THROW(bad_expected_access<error_type>(base::s.err)), base::s.val); } |
| constexpr value_type& value() & { return base::has ? base::s.val : (__EXPECTED_THROW(bad_expected_access<error_type>(base::s.err)), base::s.val); } |
| constexpr const value_type&& value() const && { return std::move(base::has ? base::s.val : (__EXPECTED_THROW(bad_expected_access<error_type>(base::s.err)), base::s.val)); } |
| constexpr value_type&& value() && { return std::move(base::has ? base::s.val : (__EXPECTED_THROW(bad_expected_access<error_type>(base::s.err)), base::s.val)); } |
| constexpr const error_type& error() const & { return !base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err); } |
| error_type& error() & { return !base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err); } |
| constexpr error_type&& error() && { return std::move(!base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err)); } |
| constexpr const error_type&& error() const && { return std::move(!base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err)); } |
| template<class U> constexpr value_type value_or(U&& u) const & { return base::has ? **this : static_cast<value_type>(std::forward<U>(u)); } |
| template<class U> value_type value_or(U&& u) && { return base::has ? std::move(**this) : static_cast<value_type>(std::forward<U>(u)); } |
| }; |
| |
| template<class E> |
| class expected<void, E> : private __expected_detail::base_select<void, E> { |
| typedef __expected_detail::base_select<void, E> base; |
| |
| public: |
| typedef typename base::value_type value_type; |
| typedef typename base::error_type error_type; |
| typedef typename base::unexpected_type unexpected_type; |
| |
| private: |
| typedef expected<value_type, error_type> type; |
| |
| public: |
| template<class U> struct rebind { |
| using type = expected<U, error_type>; |
| }; |
| |
| constexpr expected() : base(__expected_detail::value_tag) { } |
| expected(const expected&) = default; |
| expected(expected&&) = default; |
| // constexpr explicit expected(in_place_t); |
| constexpr expected(unexpected_type const& u) : base(__expected_detail::error_tag, u.value()) { } |
| constexpr expected(unexpected_type&& u) : base(__expected_detail::error_tag, std::forward<unexpected_type>(u).value()) { } |
| template<class Err> constexpr expected(unexpected<Err> const& u) : base(__expected_detail::error_tag, u.value()) { } |
| |
| ~expected() = default; |
| |
| expected& operator=(const expected& e) { type(e).swap(*this); return *this; } |
| expected& operator=(expected&& e) { type(std::move(e)).swap(*this); return *this; } |
| expected& operator=(const unexpected_type& u) { type(u).swap(*this); return *this; } // Not in the current paper. |
| expected& operator=(unexpected_type&& u) { type(std::move(u)).swap(*this); return *this; } // Not in the current paper. |
| // void emplace(); |
| |
| void swap(expected& o) |
| { |
| using std::swap; |
| if (base::has && o.has) { |
| // Do nothing. |
| } else if (base::has && !o.has) { |
| error_type e(std::move(o.s.err)); |
| ::new (std::addressof(base::s.err)) error_type(e); |
| swap(base::has, o.has); |
| } else if (!base::has && o.has) { |
| ::new (std::addressof(o.s.err)) error_type(std::move(base::s.err)); |
| swap(base::has, o.has); |
| } else |
| swap(base::s.err, o.s.err); |
| } |
| |
| constexpr explicit operator bool() const { return base::has; } |
| constexpr bool has_value() const { return base::has; } |
| void value() const { !base::has ? __EXPECTED_THROW(bad_expected_access<void>()) : void(); } |
| constexpr const E& error() const & { return !base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err); } |
| E& error() & { return !base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err); } |
| constexpr E&& error() && { return std::move(!base::has ? base::s.err : (__EXPECTED_THROW(bad_expected_access<void>()), base::s.err)); } |
| }; |
| |
| template<class T, class E> constexpr bool operator==(const expected<T, E>& x, const expected<T, E>& y) { return bool(x) == bool(y) && (x ? x.value() == y.value() : x.error() == y.error()); } |
| template<class T, class E> constexpr bool operator!=(const expected<T, E>& x, const expected<T, E>& y) { return !(x == y); } |
| |
| template<class E> constexpr bool operator==(const expected<void, E>& x, const expected<void, E>& y) { return bool(x) == bool(y) && (x ? true : x.error() == y.error()); } |
| |
| template<class T, class E> constexpr bool operator==(const expected<T, E>& x, const T& y) { return x ? *x == y : false; } |
| template<class T, class E> constexpr bool operator==(const T& x, const expected<T, E>& y) { return y ? x == *y : false; } |
| template<class T, class E> constexpr bool operator!=(const expected<T, E>& x, const T& y) { return x ? *x != y : true; } |
| template<class T, class E> constexpr bool operator!=(const T& x, const expected<T, E>& y) { return y ? x != *y : true; } |
| |
| template<class T, class E> constexpr bool operator==(const expected<T, E>& x, const unexpected<E>& y) { return x ? false : x.error() == y.value(); } |
| template<class T, class E> constexpr bool operator==(const unexpected<E>& x, const expected<T, E>& y) { return y ? false : x.value() == y.error(); } |
| template<class T, class E> constexpr bool operator!=(const expected<T, E>& x, const unexpected<E>& y) { return x ? true : x.error() != y.value(); } |
| template<class T, class E> constexpr bool operator!=(const unexpected<E>& x, const expected<T, E>& y) { return y ? true : x.value() != y.error(); } |
| |
| template<typename T, typename E> void swap(expected<T, E>& x, expected<T, E>& y) { x.swap(y); } |
| |
| }}} // namespace std::experimental::fundamentals_v3 |
| |
| __EXPECTED_INLINE_VARIABLE constexpr auto& unexpect = std::experimental::unexpect; |
| template<class T, class E> using Expected = std::experimental::expected<T, E>; |
