From c382ce52602b6ee154fad02bb5e229e86aaba645 Mon Sep 17 00:00:00 2001 From: Vincent Lejeune Date: Tue, 9 Aug 2016 20:16:47 +0200 Subject: [PATCH] Add optional files. --- Utilities/LICENSE_1_0.txt | 23 + Utilities/copyright.txt | 10 + Utilities/optional.hpp | 1039 +++++++++++++++++++++++++++++++++++++ 3 files changed, 1072 insertions(+) create mode 100644 Utilities/LICENSE_1_0.txt create mode 100644 Utilities/copyright.txt create mode 100644 Utilities/optional.hpp diff --git a/Utilities/LICENSE_1_0.txt b/Utilities/LICENSE_1_0.txt new file mode 100644 index 0000000000..36b7cd93cd --- /dev/null +++ b/Utilities/LICENSE_1_0.txt @@ -0,0 +1,23 @@ +Boost Software License - Version 1.0 - August 17th, 2003 + +Permission is hereby granted, free of charge, to any person or organization +obtaining a copy of the software and accompanying documentation covered by +this license (the "Software") to use, reproduce, display, distribute, +execute, and transmit the Software, and to prepare derivative works of the +Software, and to permit third-parties to whom the Software is furnished to +do so, all subject to the following: + +The copyright notices in the Software and this entire statement, including +the above license grant, this restriction and the following disclaimer, +must be included in all copies of the Software, in whole or in part, and +all derivative works of the Software, unless such copies or derivative +works are solely in the form of machine-executable object code generated by +a source language processor. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT +SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE +FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, +ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/Utilities/copyright.txt b/Utilities/copyright.txt new file mode 100644 index 0000000000..1641c3cdd0 --- /dev/null +++ b/Utilities/copyright.txt @@ -0,0 +1,10 @@ +Copyright (C) 2011-2012 Andrzej Krzemienski + +Distributed under the Boost Software License, Version 1.0 +(see accompanying file LICENSE_1_0.txt or a copy at +http://www.boost.org/LICENSE_1_0.txt) + +The idea and interface is based on Boost.Optional library +authored by Fernando Luis Cacciola Carballal + +Home at https://github.com/akrzemi1/Optional \ No newline at end of file diff --git a/Utilities/optional.hpp b/Utilities/optional.hpp new file mode 100644 index 0000000000..7ee842390f --- /dev/null +++ b/Utilities/optional.hpp @@ -0,0 +1,1039 @@ +// Copyright (C) 2011 - 2012 Andrzej Krzemienski. +// +// Use, modification, and distribution is subject to the Boost Software +// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +// +// The idea and interface is based on Boost.Optional library +// authored by Fernando Luis Cacciola Carballal + +# ifndef ___OPTIONAL_HPP___ +# define ___OPTIONAL_HPP___ + +# include +# include +# include +# include +# include +# include +# include + +# define TR2_OPTIONAL_REQUIRES(...) typename enable_if<__VA_ARGS__::value, bool>::type = false + +# if defined __GNUC__ // NOTE: GNUC is also defined for Clang +# if (__GNUC__ == 4) && (__GNUC_MINOR__ >= 8) +# define TR2_OPTIONAL_GCC_4_8_AND_HIGHER___ +# elif (__GNUC__ > 4) +# define TR2_OPTIONAL_GCC_4_8_AND_HIGHER___ +# endif +# +# if (__GNUC__ == 4) && (__GNUC_MINOR__ >= 7) +# define TR2_OPTIONAL_GCC_4_7_AND_HIGHER___ +# elif (__GNUC__ > 4) +# define TR2_OPTIONAL_GCC_4_7_AND_HIGHER___ +# endif +# +# if (__GNUC__ == 4) && (__GNUC_MINOR__ == 8) && (__GNUC_PATCHLEVEL__ >= 1) +# define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___ +# elif (__GNUC__ == 4) && (__GNUC_MINOR__ >= 9) +# define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___ +# elif (__GNUC__ > 4) +# define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___ +# endif +# endif +# +# if defined __clang_major__ +# if (__clang_major__ == 3 && __clang_minor__ >= 5) +# define TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_ +# elif (__clang_major__ > 3) +# define TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_ +# endif +# if defined TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_ +# define TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_ +# elif (__clang_major__ == 3 && __clang_minor__ == 4 && __clang_patchlevel__ >= 2) +# define TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_ +# endif +# endif +# +# if defined _MSC_VER +# if (_MSC_VER >= 1900) +# define TR2_OPTIONAL_MSVC_2015_AND_HIGHER___ +# endif +# endif + +# if defined __clang__ +# if (__clang_major__ > 2) || (__clang_major__ == 2) && (__clang_minor__ >= 9) +# define OPTIONAL_HAS_THIS_RVALUE_REFS 1 +# else +# define OPTIONAL_HAS_THIS_RVALUE_REFS 0 +# endif +# elif defined TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___ +# define OPTIONAL_HAS_THIS_RVALUE_REFS 1 +# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___ +# define OPTIONAL_HAS_THIS_RVALUE_REFS 1 +# else +# define OPTIONAL_HAS_THIS_RVALUE_REFS 0 +# endif + + +# if defined TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___ +# define OPTIONAL_HAS_CONSTEXPR_INIT_LIST 1 +# define OPTIONAL_CONSTEXPR_INIT_LIST constexpr +# else +# define OPTIONAL_HAS_CONSTEXPR_INIT_LIST 0 +# define OPTIONAL_CONSTEXPR_INIT_LIST +# endif + +# if defined TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_ && (defined __cplusplus) && (__cplusplus != 201103L) +# define OPTIONAL_HAS_MOVE_ACCESSORS 1 +# else +# define OPTIONAL_HAS_MOVE_ACCESSORS 0 +# endif + +# // In C++11 constexpr implies const, so we need to make non-const members also non-constexpr +# if (defined __cplusplus) && (__cplusplus == 201103L) +# define OPTIONAL_MUTABLE_CONSTEXPR +# else +# define OPTIONAL_MUTABLE_CONSTEXPR constexpr +# endif + +namespace std{ + +// BEGIN workaround for missing is_trivially_destructible +# if defined TR2_OPTIONAL_GCC_4_8_AND_HIGHER___ + // leave it: it is already there +# elif defined TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_ + // leave it: it is already there +# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___ + // leave it: it is already there +# elif defined TR2_OPTIONAL_DISABLE_EMULATION_OF_TYPE_TRAITS + // leave it: the user doesn't want it +# else + template + using is_trivially_destructible = std::has_trivial_destructor; +# endif +// END workaround for missing is_trivially_destructible + +# if (defined TR2_OPTIONAL_GCC_4_7_AND_HIGHER___) + // leave it; our metafunctions are already defined. +# elif defined TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_ + // leave it; our metafunctions are already defined. +# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___ + // leave it: it is already there +# elif defined TR2_OPTIONAL_DISABLE_EMULATION_OF_TYPE_TRAITS + // leave it: the user doesn't want it +# else + + +// workaround for missing traits in GCC and CLANG +template +struct is_nothrow_move_constructible +{ + constexpr static bool value = std::is_nothrow_constructible::value; +}; + + +template +struct is_assignable +{ + template + constexpr static bool has_assign(...) { return false; } + + template () = std::declval(), true)) > + // the comma operator is necessary for the cases where operator= returns void + constexpr static bool has_assign(bool) { return true; } + + constexpr static bool value = has_assign(true); +}; + + +template +struct is_nothrow_move_assignable +{ + template + struct has_nothrow_move_assign { + constexpr static bool value = false; + }; + + template + struct has_nothrow_move_assign { + constexpr static bool value = noexcept( std::declval() = std::declval() ); + }; + + constexpr static bool value = has_nothrow_move_assign::value>::value; +}; +// end workaround + + +# endif + + + +// 20.5.4, optional for object types +template class optional; + +// 20.5.5, optional for lvalue reference types +template class optional; + + +// workaround: std utility functions aren't constexpr yet +template inline constexpr T&& constexpr_forward(typename std::remove_reference::type& t) noexcept +{ + return static_cast(t); +} + +template inline constexpr T&& constexpr_forward(typename std::remove_reference::type&& t) noexcept +{ + static_assert(!std::is_lvalue_reference::value, "!!"); + return static_cast(t); +} + +template inline constexpr typename std::remove_reference::type&& constexpr_move(T&& t) noexcept +{ + return static_cast::type&&>(t); +} + + +#if defined NDEBUG +# define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) (EXPR) +#else +# define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) ((CHECK) ? (EXPR) : ([]{assert(!#CHECK);}(), (EXPR))) +#endif + + +namespace detail_ +{ + +// static_addressof: a constexpr version of addressof +template +struct has_overloaded_addressof +{ + template + constexpr static bool has_overload(...) { return false; } + + template ().operator&()) > + constexpr static bool has_overload(bool) { return true; } + + constexpr static bool value = has_overload(true); +}; + +template )> +constexpr T* static_addressof(T& ref) +{ + return &ref; +} + +template )> +T* static_addressof(T& ref) +{ + return std::addressof(ref); +} + + +// the call to convert(b) has return type A and converts b to type A iff b decltype(b) is implicitly convertible to A +template +constexpr U convert(U v) { return v; } + +} // namespace detail + + +constexpr struct trivial_init_t{} trivial_init{}; + + +// 20.5.6, In-place construction +constexpr struct in_place_t{} in_place{}; + + +// 20.5.7, Disengaged state indicator +struct nullopt_t +{ + struct init{}; + constexpr explicit nullopt_t(init){} +}; +constexpr nullopt_t nullopt{nullopt_t::init()}; + + +// 20.5.8, class bad_optional_access +class bad_optional_access : public logic_error { +public: + explicit bad_optional_access(const string& what_arg) : logic_error{what_arg} {} + explicit bad_optional_access(const char* what_arg) : logic_error{what_arg} {} +}; + + +template +union storage_t +{ + unsigned char dummy_; + T value_; + + constexpr storage_t( trivial_init_t ) noexcept : dummy_() {}; + + template + constexpr storage_t( Args&&... args ) : value_(constexpr_forward(args)...) {} + + ~storage_t(){} +}; + + +template +union constexpr_storage_t +{ + unsigned char dummy_; + T value_; + + constexpr constexpr_storage_t( trivial_init_t ) noexcept : dummy_() {}; + + template + constexpr constexpr_storage_t( Args&&... args ) : value_(constexpr_forward(args)...) {} + + ~constexpr_storage_t() = default; +}; + + +template +struct optional_base +{ + bool init_; + storage_t storage_; + + constexpr optional_base() noexcept : init_(false), storage_(trivial_init) {}; + + explicit constexpr optional_base(const T& v) : init_(true), storage_(v) {} + + explicit constexpr optional_base(T&& v) : init_(true), storage_(constexpr_move(v)) {} + + template explicit optional_base(in_place_t, Args&&... args) + : init_(true), storage_(constexpr_forward(args)...) {} + + template >)> + explicit optional_base(in_place_t, std::initializer_list il, Args&&... args) + : init_(true), storage_(il, std::forward(args)...) {} + + ~optional_base() { if (init_) storage_.value_.T::~T(); } +}; + + +template +struct constexpr_optional_base +{ + bool init_; + constexpr_storage_t storage_; + + constexpr constexpr_optional_base() noexcept : init_(false), storage_(trivial_init) {}; + + explicit constexpr constexpr_optional_base(const T& v) : init_(true), storage_(v) {} + + explicit constexpr constexpr_optional_base(T&& v) : init_(true), storage_(constexpr_move(v)) {} + + template explicit constexpr constexpr_optional_base(in_place_t, Args&&... args) + : init_(true), storage_(constexpr_forward(args)...) {} + + template >)> + OPTIONAL_CONSTEXPR_INIT_LIST explicit constexpr_optional_base(in_place_t, std::initializer_list il, Args&&... args) + : init_(true), storage_(il, std::forward(args)...) {} + + ~constexpr_optional_base() = default; +}; + +template +using OptionalBase = typename std::conditional< + is_trivially_destructible::value, + constexpr_optional_base::type>, + optional_base::type> +>::type; + + + +template +class optional : private OptionalBase +{ + static_assert( !std::is_same::type, nullopt_t>::value, "bad T" ); + static_assert( !std::is_same::type, in_place_t>::value, "bad T" ); + + + constexpr bool initialized() const noexcept { return OptionalBase::init_; } + typename std::remove_const::type* dataptr() { return std::addressof(OptionalBase::storage_.value_); } + constexpr const T* dataptr() const { return detail_::static_addressof(OptionalBase::storage_.value_); } + +# if OPTIONAL_HAS_THIS_RVALUE_REFS == 1 + constexpr const T& contained_val() const& { return OptionalBase::storage_.value_; } +# if OPTIONAL_HAS_MOVE_ACCESSORS == 1 + OPTIONAL_MUTABLE_CONSTEXPR T&& contained_val() && { return std::move(OptionalBase::storage_.value_); } + OPTIONAL_MUTABLE_CONSTEXPR T& contained_val() & { return OptionalBase::storage_.value_; } +# else + T& contained_val() & { return OptionalBase::storage_.value_; } + T&& contained_val() && { return std::move(OptionalBase::storage_.value_); } +# endif +# else + constexpr const T& contained_val() const { return OptionalBase::storage_.value_; } + T& contained_val() { return OptionalBase::storage_.value_; } +# endif + + void clear() noexcept { + if (initialized()) dataptr()->T::~T(); + OptionalBase::init_ = false; + } + + template + void initialize(Args&&... args) noexcept(noexcept(T(std::forward(args)...))) + { + assert(!OptionalBase::init_); + ::new (static_cast(dataptr())) T(std::forward(args)...); + OptionalBase::init_ = true; + } + + template + void initialize(std::initializer_list il, Args&&... args) noexcept(noexcept(T(il, std::forward(args)...))) + { + assert(!OptionalBase::init_); + ::new (static_cast(dataptr())) T(il, std::forward(args)...); + OptionalBase::init_ = true; + } + +public: + typedef T value_type; + + // 20.5.5.1, constructors + constexpr optional() noexcept : OptionalBase() {}; + constexpr optional(nullopt_t) noexcept : OptionalBase() {}; + + optional(const optional& rhs) + : OptionalBase() + { + if (rhs.initialized()) { + ::new (static_cast(dataptr())) T(*rhs); + OptionalBase::init_ = true; + } + } + + optional(optional&& rhs) noexcept(is_nothrow_move_constructible::value) + : OptionalBase() + { + if (rhs.initialized()) { + ::new (static_cast(dataptr())) T(std::move(*rhs)); + OptionalBase::init_ = true; + } + } + + constexpr optional(const T& v) : OptionalBase(v) {} + + constexpr optional(T&& v) : OptionalBase(constexpr_move(v)) {} + + template + explicit constexpr optional(in_place_t, Args&&... args) + : OptionalBase(in_place_t{}, constexpr_forward(args)...) {} + + template >)> + OPTIONAL_CONSTEXPR_INIT_LIST explicit optional(in_place_t, std::initializer_list il, Args&&... args) + : OptionalBase(in_place_t{}, il, constexpr_forward(args)...) {} + + // 20.5.4.2, Destructor + ~optional() = default; + + // 20.5.4.3, assignment + optional& operator=(nullopt_t) noexcept + { + clear(); + return *this; + } + + optional& operator=(const optional& rhs) + { + if (initialized() == true && rhs.initialized() == false) clear(); + else if (initialized() == false && rhs.initialized() == true) initialize(*rhs); + else if (initialized() == true && rhs.initialized() == true) contained_val() = *rhs; + return *this; + } + + optional& operator=(optional&& rhs) + noexcept(is_nothrow_move_assignable::value && is_nothrow_move_constructible::value) + { + if (initialized() == true && rhs.initialized() == false) clear(); + else if (initialized() == false && rhs.initialized() == true) initialize(std::move(*rhs)); + else if (initialized() == true && rhs.initialized() == true) contained_val() = std::move(*rhs); + return *this; + } + + template + auto operator=(U&& v) + -> typename enable_if + < + is_same::type, T>::value, + optional& + >::type + { + if (initialized()) { contained_val() = std::forward(v); } + else { initialize(std::forward(v)); } + return *this; + } + + + template + void emplace(Args&&... args) + { + clear(); + initialize(std::forward(args)...); + } + + template + void emplace(initializer_list il, Args&&... args) + { + clear(); + initialize(il, std::forward(args)...); + } + + // 20.5.4.4, Swap + void swap(optional& rhs) noexcept(is_nothrow_move_constructible::value && noexcept(swap(declval(), declval()))) + { + if (initialized() == true && rhs.initialized() == false) { rhs.initialize(std::move(**this)); clear(); } + else if (initialized() == false && rhs.initialized() == true) { initialize(std::move(*rhs)); rhs.clear(); } + else if (initialized() == true && rhs.initialized() == true) { using std::swap; swap(**this, *rhs); } + } + + // 20.5.4.5, Observers + + explicit constexpr operator bool() const noexcept { return initialized(); } + + constexpr T const* operator ->() const { + return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), dataptr()); + } + +# if OPTIONAL_HAS_MOVE_ACCESSORS == 1 + + OPTIONAL_MUTABLE_CONSTEXPR T* operator ->() { + assert (initialized()); + return dataptr(); + } + + constexpr T const& operator *() const& { + return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val()); + } + + OPTIONAL_MUTABLE_CONSTEXPR T& operator *() & { + assert (initialized()); + return contained_val(); + } + + OPTIONAL_MUTABLE_CONSTEXPR T&& operator *() && { + assert (initialized()); + return constexpr_move(contained_val()); + } + + constexpr T const& value() const& { + return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val()); + } + + OPTIONAL_MUTABLE_CONSTEXPR T& value() & { + return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val()); + } + + OPTIONAL_MUTABLE_CONSTEXPR T&& value() && { + if (!initialized()) throw bad_optional_access("bad optional access"); + return std::move(contained_val()); + } + +# else + + T* operator ->() { + assert (initialized()); + return dataptr(); + } + + constexpr T const& operator *() const { + return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val()); + } + + T& operator *() { + assert (initialized()); + return contained_val(); + } + + constexpr T const& value() const { + return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val()); + } + + T& value() { + return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val()); + } + +# endif + +# if OPTIONAL_HAS_THIS_RVALUE_REFS == 1 + + template + constexpr T value_or(V&& v) const& + { + return *this ? **this : detail_::convert(constexpr_forward(v)); + } + +# if OPTIONAL_HAS_MOVE_ACCESSORS == 1 + + template + OPTIONAL_MUTABLE_CONSTEXPR T value_or(V&& v) && + { + return *this ? constexpr_move(const_cast&>(*this).contained_val()) : detail_::convert(constexpr_forward(v)); + } + +# else + + template + T value_or(V&& v) && + { + return *this ? constexpr_move(const_cast&>(*this).contained_val()) : detail_::convert(constexpr_forward(v)); + } + +# endif + +# else + + template + constexpr T value_or(V&& v) const + { + return *this ? **this : detail_::convert(constexpr_forward(v)); + } + +# endif + +}; + + +template +class optional +{ + static_assert( !std::is_same::value, "bad T" ); + static_assert( !std::is_same::value, "bad T" ); + T* ref; + +public: + + // 20.5.5.1, construction/destruction + constexpr optional() noexcept : ref(nullptr) {} + + constexpr optional(nullopt_t) noexcept : ref(nullptr) {} + + constexpr optional(T& v) noexcept : ref(detail_::static_addressof(v)) {} + + optional(T&&) = delete; + + constexpr optional(const optional& rhs) noexcept : ref(rhs.ref) {} + + explicit constexpr optional(in_place_t, T& v) noexcept : ref(detail_::static_addressof(v)) {} + + explicit optional(in_place_t, T&&) = delete; + + ~optional() = default; + + // 20.5.5.2, mutation + optional& operator=(nullopt_t) noexcept { + ref = nullptr; + return *this; + } + + // optional& operator=(const optional& rhs) noexcept { + // ref = rhs.ref; + // return *this; + // } + + // optional& operator=(optional&& rhs) noexcept { + // ref = rhs.ref; + // return *this; + // } + + template + auto operator=(U&& rhs) noexcept + -> typename enable_if + < + is_same::type, optional>::value, + optional& + >::type + { + ref = rhs.ref; + return *this; + } + + template + auto operator=(U&& rhs) noexcept + -> typename enable_if + < + !is_same::type, optional>::value, + optional& + >::type + = delete; + + void emplace(T& v) noexcept { + ref = detail_::static_addressof(v); + } + + void emplace(T&&) = delete; + + + void swap(optional& rhs) noexcept + { + std::swap(ref, rhs.ref); + } + + // 20.5.5.3, observers + constexpr T* operator->() const { + return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, ref); + } + + constexpr T& operator*() const { + return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, *ref); + } + + constexpr T& value() const { + return ref ? *ref : (throw bad_optional_access("bad optional access"), *ref); + } + + explicit constexpr operator bool() const noexcept { + return ref != nullptr; + } + + template + constexpr typename decay::type value_or(V&& v) const + { + return *this ? **this : detail_::convert::type>(constexpr_forward(v)); + } +}; + + +template +class optional +{ + static_assert( sizeof(T) == 0, "optional rvalue references disallowed" ); +}; + + +// 20.5.8, Relational operators +template constexpr bool operator==(const optional& x, const optional& y) +{ + return bool(x) != bool(y) ? false : bool(x) == false ? true : *x == *y; +} + +template constexpr bool operator!=(const optional& x, const optional& y) +{ + return !(x == y); +} + +template constexpr bool operator<(const optional& x, const optional& y) +{ + return (!y) ? false : (!x) ? true : *x < *y; +} + +template constexpr bool operator>(const optional& x, const optional& y) +{ + return (y < x); +} + +template constexpr bool operator<=(const optional& x, const optional& y) +{ + return !(y < x); +} + +template constexpr bool operator>=(const optional& x, const optional& y) +{ + return !(x < y); +} + + +// 20.5.9, Comparison with nullopt +template constexpr bool operator==(const optional& x, nullopt_t) noexcept +{ + return (!x); +} + +template constexpr bool operator==(nullopt_t, const optional& x) noexcept +{ + return (!x); +} + +template constexpr bool operator!=(const optional& x, nullopt_t) noexcept +{ + return bool(x); +} + +template constexpr bool operator!=(nullopt_t, const optional& x) noexcept +{ + return bool(x); +} + +template constexpr bool operator<(const optional&, nullopt_t) noexcept +{ + return false; +} + +template constexpr bool operator<(nullopt_t, const optional& x) noexcept +{ + return bool(x); +} + +template constexpr bool operator<=(const optional& x, nullopt_t) noexcept +{ + return (!x); +} + +template constexpr bool operator<=(nullopt_t, const optional&) noexcept +{ + return true; +} + +template constexpr bool operator>(const optional& x, nullopt_t) noexcept +{ + return bool(x); +} + +template constexpr bool operator>(nullopt_t, const optional&) noexcept +{ + return false; +} + +template constexpr bool operator>=(const optional&, nullopt_t) noexcept +{ + return true; +} + +template constexpr bool operator>=(nullopt_t, const optional& x) noexcept +{ + return (!x); +} + + + +// 20.5.10, Comparison with T +template constexpr bool operator==(const optional& x, const T& v) +{ + return bool(x) ? *x == v : false; +} + +template constexpr bool operator==(const T& v, const optional& x) +{ + return bool(x) ? v == *x : false; +} + +template constexpr bool operator!=(const optional& x, const T& v) +{ + return bool(x) ? *x != v : true; +} + +template constexpr bool operator!=(const T& v, const optional& x) +{ + return bool(x) ? v != *x : true; +} + +template constexpr bool operator<(const optional& x, const T& v) +{ + return bool(x) ? *x < v : true; +} + +template constexpr bool operator>(const T& v, const optional& x) +{ + return bool(x) ? v > *x : true; +} + +template constexpr bool operator>(const optional& x, const T& v) +{ + return bool(x) ? *x > v : false; +} + +template constexpr bool operator<(const T& v, const optional& x) +{ + return bool(x) ? v < *x : false; +} + +template constexpr bool operator>=(const optional& x, const T& v) +{ + return bool(x) ? *x >= v : false; +} + +template constexpr bool operator<=(const T& v, const optional& x) +{ + return bool(x) ? v <= *x : false; +} + +template constexpr bool operator<=(const optional& x, const T& v) +{ + return bool(x) ? *x <= v : true; +} + +template constexpr bool operator>=(const T& v, const optional& x) +{ + return bool(x) ? v >= *x : true; +} + + +// Comparison of optional with T +template constexpr bool operator==(const optional& x, const T& v) +{ + return bool(x) ? *x == v : false; +} + +template constexpr bool operator==(const T& v, const optional& x) +{ + return bool(x) ? v == *x : false; +} + +template constexpr bool operator!=(const optional& x, const T& v) +{ + return bool(x) ? *x != v : true; +} + +template constexpr bool operator!=(const T& v, const optional& x) +{ + return bool(x) ? v != *x : true; +} + +template constexpr bool operator<(const optional& x, const T& v) +{ + return bool(x) ? *x < v : true; +} + +template constexpr bool operator>(const T& v, const optional& x) +{ + return bool(x) ? v > *x : true; +} + +template constexpr bool operator>(const optional& x, const T& v) +{ + return bool(x) ? *x > v : false; +} + +template constexpr bool operator<(const T& v, const optional& x) +{ + return bool(x) ? v < *x : false; +} + +template constexpr bool operator>=(const optional& x, const T& v) +{ + return bool(x) ? *x >= v : false; +} + +template constexpr bool operator<=(const T& v, const optional& x) +{ + return bool(x) ? v <= *x : false; +} + +template constexpr bool operator<=(const optional& x, const T& v) +{ + return bool(x) ? *x <= v : true; +} + +template constexpr bool operator>=(const T& v, const optional& x) +{ + return bool(x) ? v >= *x : true; +} + +// Comparison of optional with T +template constexpr bool operator==(const optional& x, const T& v) +{ + return bool(x) ? *x == v : false; +} + +template constexpr bool operator==(const T& v, const optional& x) +{ + return bool(x) ? v == *x : false; +} + +template constexpr bool operator!=(const optional& x, const T& v) +{ + return bool(x) ? *x != v : true; +} + +template constexpr bool operator!=(const T& v, const optional& x) +{ + return bool(x) ? v != *x : true; +} + +template constexpr bool operator<(const optional& x, const T& v) +{ + return bool(x) ? *x < v : true; +} + +template constexpr bool operator>(const T& v, const optional& x) +{ + return bool(x) ? v > *x : true; +} + +template constexpr bool operator>(const optional& x, const T& v) +{ + return bool(x) ? *x > v : false; +} + +template constexpr bool operator<(const T& v, const optional& x) +{ + return bool(x) ? v < *x : false; +} + +template constexpr bool operator>=(const optional& x, const T& v) +{ + return bool(x) ? *x >= v : false; +} + +template constexpr bool operator<=(const T& v, const optional& x) +{ + return bool(x) ? v <= *x : false; +} + +template constexpr bool operator<=(const optional& x, const T& v) +{ + return bool(x) ? *x <= v : true; +} + +template constexpr bool operator>=(const T& v, const optional& x) +{ + return bool(x) ? v >= *x : true; +} + + +// 20.5.12, Specialized algorithms +template +void swap(optional& x, optional& y) noexcept(noexcept(x.swap(y))) +{ + x.swap(y); +} + + +template +constexpr optional::type> make_optional(T&& v) +{ + return optional::type>(constexpr_forward(v)); +} + +template +constexpr optional make_optional(reference_wrapper v) +{ + return optional(v.get()); +} + + +} // namespace std + +namespace std +{ + template + struct hash> + { + typedef typename hash::result_type result_type; + typedef std::optional argument_type; + + constexpr result_type operator()(argument_type const& arg) const { + return arg ? std::hash{}(*arg) : result_type{}; + } + }; + + template + struct hash> + { + typedef typename hash::result_type result_type; + typedef std::optional argument_type; + + constexpr result_type operator()(argument_type const& arg) const { + return arg ? std::hash{}(*arg) : result_type{}; + } + }; +} + +# undef TR2_OPTIONAL_REQUIRES +# undef TR2_OPTIONAL_ASSERTED_EXPRESSION + +# endif //___OPTIONAL_HPP___