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--- a/cppdraft/expected/void/assign.md
+++ b/cppdraft/expected/void/assign.md
@@ -0,0 +1,148 @@
+[expected.void.assign]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.assign)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#assign)
+
+#### 22.8.7.4 Assignment [expected.void.assign]
+
+[ð](#lib:operator=,expected%3cvoid%3e)
+
+`constexpr expected& operator=(const expected& rhs);
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9771)
+
+*Effects*: 
+
+- [(1.1)](#1.1)
+
+  If this->has_value() && rhs.has_value() is true, no effects[.](#1.1.sentence-1)
+
+- [(1.2)](#1.2)
+
+  Otherwise, if this->has_value() is true,
+equivalent to: construct_at(addressof(*unex*), rhs.*unex*); *has_val* = false;
+
+- [(1.3)](#1.3)
+
+  Otherwise, if rhs.has_value() is true,
+destroys *unex* and sets *has_val* to true[.](#1.3.sentence-1)
+
+- [(1.4)](#1.4)
+
+  Otherwise, equivalent to *unex* = rhs.error()[.](#1.4.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9786)
+
+*Returns*: *this[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9790)
+
+*Remarks*: This operator is defined as deleted unlessis_copy_assignable_v<E> is true andis_copy_constructible_v<E> is true[.](#3.sentence-1)
+
+[ð](#lib:operator=,expected%3cvoid%3e_)
+
+`constexpr expected& operator=(expected&& rhs) noexcept(see below);
+`
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9803)
+
+*Constraints*: is_move_constructible_v<E> is true andis_move_assignable_v<E> is true[.](#4.sentence-1)
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9808)
+
+*Effects*: 
+
+- [(5.1)](#5.1)
+
+  If this->has_value() && rhs.has_value() is true, no effects[.](#5.1.sentence-1)
+
+- [(5.2)](#5.2)
+
+  Otherwise, if this->has_value() is true, equivalent to:construct_at(addressof(*unex*), std::move(rhs.*unex*));*has_val* = false;
+
+- [(5.3)](#5.3)
+
+  Otherwise, if rhs.has_value() is true,
+destroys *unex* and sets *has_val* to true[.](#5.3.sentence-1)
+
+- [(5.4)](#5.4)
+
+  Otherwise, equivalent to *unex* = std::move(rhs.error())[.](#5.4.sentence-1)
+
+[6](#6)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9826)
+
+*Returns*: *this[.](#6.sentence-1)
+
+[7](#7)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9830)
+
+*Remarks*: The exception specification is equivalent tois_nothrow_move_constructible_v<E> && is_nothrow_move_assignable_v<E>[.](#7.sentence-1)
+
+[ð](#lib:operator=,expected%3cvoid%3e__)
+
+`template<class G>
+  constexpr expected& operator=(const unexpected<G>& e);
+template<class G>
+  constexpr expected& operator=(unexpected<G>&& e);
+`
+
+[8](#8)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9845)
+
+Let GF be const G& for the first overload andG for the second overload[.](#8.sentence-1)
+
+[9](#9)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9849)
+
+*Constraints*: is_constructible_v<E, GF> is true andis_assignable_v<E&, GF> is true[.](#9.sentence-1)
+
+[10](#10)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9854)
+
+*Effects*: 
+
+- [(10.1)](#10.1)
+
+If has_value() is true, equivalent to:construct_at(addressof(*unex*), std::forward<GF>(e.error()));*has_val* = false;
+
+- [(10.2)](#10.2)
+
+Otherwise, equivalent to:*unex* = std::forward<GF>(e.error());
+
+[11](#11)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9868)
+
+*Returns*: *this[.](#11.sentence-1)
+
+[ð](#lib:emplace,expected%3cvoid%3e)
+
+`constexpr void emplace() noexcept;
+`
+
+[12](#12)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9879)
+
+*Effects*: If has_value() is false,
+destroys *unex* and sets *has_val* to true[.](#12.sentence-1)
--- a/cppdraft/expected/void/cons.md
+++ b/cppdraft/expected/void/cons.md
@@ -0,0 +1,267 @@
+[expected.void.cons]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.cons)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#cons)
+
+#### 22.8.7.2 Constructors [expected.void.cons]
+
+[ð](#lib:expected%3cvoid%3e,constructor)
+
+`constexpr expected() noexcept;
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9539)
+
+*Postconditions*: has_value() is true[.](#1.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor_)
+
+`constexpr expected(const expected& rhs);
+`
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9550)
+
+*Effects*: If rhs.has_value() is false,
+direct-non-list-initializes *unex* with rhs.error()[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9555)
+
+*Postconditions*: rhs.has_value() == this->has_value()[.](#3.sentence-1)
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9559)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#4.sentence-1)
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9563)
+
+*Remarks*: This constructor is defined as deleted
+unless is_copy_constructible_v<E> is true[.](#5.sentence-1)
+
+[6](#6)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9568)
+
+This constructor is trivial
+if is_trivially_copy_constructible_v<E> is true[.](#6.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor__)
+
+`constexpr expected(expected&& rhs) noexcept(is_nothrow_move_constructible_v<E>);
+`
+
+[7](#7)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9579)
+
+*Constraints*: is_move_constructible_v<E> is true[.](#7.sentence-1)
+
+[8](#8)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9583)
+
+*Effects*: If rhs.has_value() is false,
+direct-non-list-initializes *unex* with std::move(rhs.error())[.](#8.sentence-1)
+
+[9](#9)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9588)
+
+*Postconditions*: rhs.has_value() is unchanged;rhs.has_value() == this->has_value() is true[.](#9.sentence-1)
+
+[10](#10)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9593)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#10.sentence-1)
+
+[11](#11)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9597)
+
+*Remarks*: This constructor is trivial
+if is_trivially_move_constructible_v<E> is true[.](#11.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor___)
+
+`template<class U, class G>
+  constexpr explicit(!is_convertible_v<const G&, E>) expected(const expected<U, G>& rhs);
+template<class U, class G>
+  constexpr explicit(!is_convertible_v<G, E>) expected(expected<U, G>&& rhs);
+`
+
+[12](#12)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9612)
+
+Let GF be const G& for the first overload andG for the second overload[.](#12.sentence-1)
+
+[13](#13)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9616)
+
+*Constraints*: 
+
+- [(13.1)](#13.1)
+
+is_void_v<U> is true; and
+
+- [(13.2)](#13.2)
+
+is_constructible_v<E, GF> is true; and
+
+- [(13.3)](#13.3)
+
+is_constructible_v<unexpected<E>, expected<U, G>&> is false; and
+
+- [(13.4)](#13.4)
+
+is_constructible_v<unexpected<E>, expected<U, G>> is false; and
+
+- [(13.5)](#13.5)
+
+is_constructible_v<unexpected<E>, const expected<U, G>&> is false; and
+
+- [(13.6)](#13.6)
+
+is_constructible_v<unexpected<E>, const expected<U, G>> is false[.](#13.sentence-1)
+
+[14](#14)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9637)
+
+*Effects*: If rhs.has_value() is false,
+direct-non-list-initializes *unex* with std::forward<GF>(rhs.error())[.](#14.sentence-1)
+
+[15](#15)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9643)
+
+*Postconditions*: rhs.has_value() is unchanged;rhs.has_value() == this->has_value() is true[.](#15.sentence-1)
+
+[16](#16)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9648)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#16.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor____)
+
+`template<class G>
+  constexpr explicit(!is_convertible_v<const G&, E>) expected(const unexpected<G>& e);
+template<class G>
+  constexpr explicit(!is_convertible_v<G, E>) expected(unexpected<G>&& e);
+`
+
+[17](#17)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9662)
+
+Let GF be const G& for the first overload andG for the second overload[.](#17.sentence-1)
+
+[18](#18)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9666)
+
+*Constraints*: is_constructible_v<E, GF> is true[.](#18.sentence-1)
+
+[19](#19)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9670)
+
+*Effects*: Direct-non-list-initializes *unex* with std::forward<GF>(e.error())[.](#19.sentence-1)
+
+[20](#20)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9675)
+
+*Postconditions*: has_value() is false[.](#20.sentence-1)
+
+[21](#21)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9679)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#21.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor_____)
+
+`constexpr explicit expected(in_place_t) noexcept;
+`
+
+[22](#22)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9690)
+
+*Postconditions*: has_value() is true[.](#22.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor______)
+
+`template<class... Args>
+  constexpr explicit expected(unexpect_t, Args&&... args);
+`
+
+[23](#23)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9702)
+
+*Constraints*: is_constructible_v<E, Args...> is true[.](#23.sentence-1)
+
+[24](#24)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9706)
+
+*Effects*: Direct-non-list-initializes *unex* with std::forward<Args>(args)...[.](#24.sentence-1)
+
+[25](#25)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9711)
+
+*Postconditions*: has_value() is false[.](#25.sentence-1)
+
+[26](#26)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9715)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#26.sentence-1)
+
+[ð](#lib:expected%3cvoid%3e,constructor_______)
+
+`template<class U, class... Args>
+  constexpr explicit expected(unexpect_t, initializer_list<U> il, Args&&... args);
+`
+
+[27](#27)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9727)
+
+*Constraints*: is_constructible_v<E, initializer_list<U>&, Args...> is true[.](#27.sentence-1)
+
+[28](#28)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9731)
+
+*Effects*: Direct-non-list-initializes *unex* with il, std::forward<Args>(args)...[.](#28.sentence-1)
+
+[29](#29)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9736)
+
+*Postconditions*: has_value() is false[.](#29.sentence-1)
+
+[30](#30)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9740)
+
+*Throws*: Any exception thrown by the initialization of *unex*[.](#30.sentence-1)
--- a/cppdraft/expected/void/dtor.md
+++ b/cppdraft/expected/void/dtor.md
@@ -0,0 +1,27 @@
+[expected.void.dtor]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.dtor)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#dtor)
+
+#### 22.8.7.3 Destructor [expected.void.dtor]
+
+[ð](#lib:expected%3cvoid%3e,destructor)
+
+`constexpr ~expected();
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9753)
+
+*Effects*: If has_value() is false, destroys *unex*[.](#1.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9757)
+
+*Remarks*: If is_trivially_destructible_v<E> is true,
+then this destructor is a trivial destructor[.](#2.sentence-1)
--- a/cppdraft/expected/void/eq.md
+++ b/cppdraft/expected/void/eq.md
@@ -0,0 +1,48 @@
+[expected.void.eq]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.eq)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#eq)
+
+#### 22.8.7.8 Equality operators [expected.void.eq]
+
+[ð](#lib:operator==,expected%3cvoid%3e)
+
+`template<class T2, class E2> requires is_void_v<T2>
+  friend constexpr bool operator==(const expected& x, const expected<T2, E2>& y);
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10327)
+
+*Constraints*: The expression x.error() == y.error() is well-formed and
+its result is convertible to bool[.](#1.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10332)
+
+*Returns*: If x.has_value() does not equal y.has_value(), false;
+otherwise x.has_value() || static_cast<bool>(x.error() == y.error())[.](#2.sentence-1)
+
+[ð](#lib:operator==,expected%3cvoid%3e_)
+
+`template<class E2>
+  friend constexpr bool operator==(const expected& x, const unexpected<E2>& e);
+`
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10345)
+
+*Constraints*: The expression x.error() == e.error() is well-formed and
+its result is convertible to bool[.](#3.sentence-1)
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10350)
+
+*Returns*: !x.has_value() && static_cast<bool>(x.error() == e.error())[.](#4.sentence-1)
--- a/cppdraft/expected/void/general.md
+++ b/cppdraft/expected/void/general.md
@@ -0,0 +1,39 @@
+[expected.void.general]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.general)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#general)
+
+#### 22.8.7.1 General [expected.void.general]
+
+template<class T, class E> requires is_void_v<T>class expected<T, E> {public:using [value_type](#lib:expected%3cvoid%3e,value_type "22.8.7.1 General [expected.void.general]") = T; using [error_type](#lib:expected%3cvoid%3e,error_type "22.8.7.1 General [expected.void.general]") = E; using [unexpected_type](#lib:expected%3cvoid%3e,unexpected_type "22.8.7.1 General [expected.void.general]") = unexpected<E>; template<class U>using [rebind](#lib:expected%3cvoid%3e,rebind "22.8.7.1 General [expected.void.general]") = expected<U, error_type>; // [[expected.void.cons]](expected.void.cons "22.8.7.2 Constructors"), constructorsconstexpr expected() noexcept; constexpr expected(const expected&); constexpr expected(expected&&) noexcept(*see below*); template<class U, class G>constexpr explicit(*see below*) expected(const expected<U, G>&); template<class U, class G>constexpr explicit(*see below*) expected(expected<U, G>&&); template<class G>constexpr explicit(*see below*) expected(const unexpected<G>&); template<class G>constexpr explicit(*see below*) expected(unexpected<G>&&); constexpr explicit expected(in_place_t) noexcept; template<class... Args>constexpr explicit expected(unexpect_t, Args&&...); template<class U, class... Args>constexpr explicit expected(unexpect_t, initializer_list<U>, Args&&...); // [[expected.void.dtor]](expected.void.dtor "22.8.7.3 Destructor"), destructorconstexpr ~expected(); // [[expected.void.assign]](expected.void.assign "22.8.7.4 Assignment"), assignmentconstexpr expected& operator=(const expected&); constexpr expected& operator=(expected&&) noexcept(*see below*); template<class G>constexpr expected& operator=(const unexpected<G>&); template<class G>constexpr expected& operator=(unexpected<G>&&); constexpr void emplace() noexcept; // [[expected.void.swap]](expected.void.swap "22.8.7.5 Swap"), swapconstexpr void swap(expected&) noexcept(*see below*); friend constexpr void swap(expected& x, expected& y) noexcept(noexcept(x.swap(y))); // [[expected.void.obs]](expected.void.obs "22.8.7.6 Observers"), observersconstexpr explicit operator bool() const noexcept; constexpr bool has_value() const noexcept; constexpr void operator*() const noexcept; constexpr void value() const &; // freestanding-deletedconstexpr void value() &&; // freestanding-deletedconstexpr const E& error() const & noexcept; constexpr E& error() & noexcept; constexpr const E&& error() const && noexcept; constexpr E&& error() && noexcept; template<class G = E> constexpr E error_or(G&&) const &; template<class G = E> constexpr E error_or(G&&) &&; // [[expected.void.monadic]](expected.void.monadic "22.8.7.7 Monadic operations"), monadic operationstemplate<class F> constexpr auto and_then(F&& f) &; template<class F> constexpr auto and_then(F&& f) &&; template<class F> constexpr auto and_then(F&& f) const &; template<class F> constexpr auto and_then(F&& f) const &&; template<class F> constexpr auto or_else(F&& f) &; template<class F> constexpr auto or_else(F&& f) &&; template<class F> constexpr auto or_else(F&& f) const &; template<class F> constexpr auto or_else(F&& f) const &&; template<class F> constexpr auto transform(F&& f) &; template<class F> constexpr auto transform(F&& f) &&; template<class F> constexpr auto transform(F&& f) const &; template<class F> constexpr auto transform(F&& f) const &&; template<class F> constexpr auto transform_error(F&& f) &; template<class F> constexpr auto transform_error(F&& f) &&; template<class F> constexpr auto transform_error(F&& f) const &; template<class F> constexpr auto transform_error(F&& f) const &&; // [[expected.void.eq]](expected.void.eq "22.8.7.8 Equality operators"), equality operatorstemplate<class T2, class E2> requires is_void_v<T2>friend constexpr bool operator==(const expected& x, const expected<T2, E2>& y); template<class E2>friend constexpr bool operator==(const expected&, const unexpected<E2>&);
+
+private:bool *has_val*; // *exposition only*union { E *unex*; // *exposition only*};};
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9513)
+
+Any object of type expected<T, E> either
+represents a value of type T, or
+contains a value of type E nested within ([[intro.object]](intro.object "6.8.2 Object model")) it[.](#1.sentence-1)
+
+Member *has_val* indicates whether the expected<T, E> object
+represents a value of type T[.](#1.sentence-2)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9521)
+
+A program that instantiates
+the definition of the template expected<T, E> with
+a type for the E parameter that
+is not a valid template argument for unexpected is ill-formed[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9527)
+
+E shall meet the requirements of[*Cpp17Destructible*](utility.arg.requirements#:Cpp17Destructible "16.4.4.2 Template argument requirements [utility.arg.requirements]") (Table [35](utility.arg.requirements#tab:cpp17.destructible "Table 35: Cpp17Destructible requirements"))[.](#3.sentence-1)
--- a/cppdraft/expected/void/monadic.md
+++ b/cppdraft/expected/void/monadic.md
@@ -0,0 +1,255 @@
+[expected.void.monadic]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.monadic)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#monadic)
+
+#### 22.8.7.7 Monadic operations [expected.void.monadic]
+
+[ð](#lib:and_then,expected%3cvoid%3e)
+
+`template<class F> constexpr auto and_then(F&& f) &;
+template<class F> constexpr auto and_then(F&& f) const &;
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10077)
+
+Let U be remove_cvref_t<invoke_result_t<F>>[.](#1.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10080)
+
+*Constraints*: is_constructible_v<E, decltype(error())>> is true[.](#2.sentence-1)
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10084)
+
+*Mandates*: U is a specialization of expected andis_same_v<U::error_type, E> is true[.](#3.sentence-1)
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10089)
+
+*Effects*: Equivalent to:if (has_value())return invoke(std::forward<F>(f));elsereturn U(unexpect, error());
+
+[ð](#lib:and_then,expected%3cvoid%3e_)
+
+`template<class F> constexpr auto and_then(F&& f) &&;
+template<class F> constexpr auto and_then(F&& f) const &&;
+`
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10107)
+
+Let U be remove_cvref_t<invoke_result_t<F>>[.](#5.sentence-1)
+
+[6](#6)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10110)
+
+*Constraints*: is_constructible_v<E, decltype(std::move(error()))> is true[.](#6.sentence-1)
+
+[7](#7)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10114)
+
+*Mandates*: U is a specialization of expected andis_same_v<U::error_type, E> is true[.](#7.sentence-1)
+
+[8](#8)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10119)
+
+*Effects*: Equivalent to:if (has_value())return invoke(std::forward<F>(f));elsereturn U(unexpect, std::move(error()));
+
+[ð](#lib:or_else,expected%3cvoid%3e)
+
+`template<class F> constexpr auto or_else(F&& f) &;
+template<class F> constexpr auto or_else(F&& f) const &;
+`
+
+[9](#9)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10137)
+
+Let G be remove_cvref_t<invoke_result_t<F, decltype(error())>>[.](#9.sentence-1)
+
+[10](#10)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10140)
+
+*Mandates*: G is a specialization of expected andis_same_v<G::value_type, T> is true[.](#10.sentence-1)
+
+[11](#11)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10145)
+
+*Effects*: Equivalent to:if (has_value())return G();elsereturn invoke(std::forward<F>(f), error());
+
+[ð](#lib:or_else,expected%3cvoid%3e_)
+
+`template<class F> constexpr auto or_else(F&& f) &&;
+template<class F> constexpr auto or_else(F&& f) const &&;
+`
+
+[12](#12)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10163)
+
+Let G beremove_cvref_t<invoke_result_t<F, decltype(std::move(error()))>>[.](#12.sentence-1)
+
+[13](#13)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10167)
+
+*Mandates*: G is a specialization of expected andis_same_v<G::value_type, T> is true[.](#13.sentence-1)
+
+[14](#14)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10172)
+
+*Effects*: Equivalent to:if (has_value())return G();elsereturn invoke(std::forward<F>(f), std::move(error()));
+
+[ð](#lib:transform,expected%3cvoid%3e)
+
+`template<class F> constexpr auto transform(F&& f) &;
+template<class F> constexpr auto transform(F&& f) const &;
+`
+
+[15](#15)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10190)
+
+Let U be remove_cv_t<invoke_result_t<F>>[.](#15.sentence-1)
+
+[16](#16)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10193)
+
+*Constraints*: is_constructible_v<E, decltype(error())> is true[.](#16.sentence-1)
+
+[17](#17)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10197)
+
+*Mandates*: U is a valid value type for expected[.](#17.sentence-1)
+
+If is_void_v<U> isfalse, the declarationU u(invoke(std::forward<F>(f))); is well-formed[.](#17.sentence-2)
+
+[18](#18)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10206)
+
+*Effects*: 
+
+- [(18.1)](#18.1)
+
+  If has_value() is false, returnsexpected<U, E>(unexpect, error())[.](#18.1.sentence-1)
+
+- [(18.2)](#18.2)
+
+  Otherwise, if is_void_v<U> is false, returns anexpected<U, E> object whose *has_val* member is true and*val* member is direct-non-list-initialized withinvoke(std::forward<F>(f))[.](#18.2.sentence-1)
+
+- [(18.3)](#18.3)
+
+  Otherwise, evaluates invoke(std::forward<F>(f)) and then returnsexpected<U, E>()[.](#18.3.sentence-1)
+
+[ð](#lib:transform,expected%3cvoid%3e_)
+
+`template<class F> constexpr auto transform(F&& f) &&;
+template<class F> constexpr auto transform(F&& f) const &&;
+`
+
+[19](#19)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10230)
+
+Let U be remove_cv_t<invoke_result_t<F>>[.](#19.sentence-1)
+
+[20](#20)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10233)
+
+*Constraints*: is_constructible_v<E, decltype(std::move(error()))> is true[.](#20.sentence-1)
+
+[21](#21)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10237)
+
+*Mandates*: U is a valid value type for expected[.](#21.sentence-1)
+
+If is_void_v<U> isfalse, the declarationU u(invoke(std::forward<F>(f))); is well-formed[.](#21.sentence-2)
+
+[22](#22)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10246)
+
+*Effects*: 
+
+- [(22.1)](#22.1)
+
+  If has_value() is false, returnsexpected<U, E>(unexpect, std::move(error()))[.](#22.1.sentence-1)
+
+- [(22.2)](#22.2)
+
+  Otherwise, if is_void_v<U> is false, returns anexpected<U, E> object whose *has_val* member is true and*val* member is direct-non-list-initialized withinvoke(std::forward<F>(f))[.](#22.2.sentence-1)
+
+- [(22.3)](#22.3)
+
+  Otherwise, evaluates invoke(std::forward<F>(f)) and then returnsexpected<U, E>()[.](#22.3.sentence-1)
+
+[ð](#lib:transform_error,expected%3cvoid%3e)
+
+`template<class F> constexpr auto transform_error(F&& f) &;
+template<class F> constexpr auto transform_error(F&& f) const &;
+`
+
+[23](#23)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10270)
+
+Let G be remove_cv_t<invoke_result_t<F, decltype(error())>>[.](#23.sentence-1)
+
+[24](#24)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10273)
+
+*Mandates*: G is a valid template argument
+for unexpected ([[expected.un.general]](expected.un.general "22.8.3.1 General")) and the declarationG g(invoke(std::forward<F>(f), error())); is well-formed[.](#24.sentence-1)
+
+[25](#25)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10282)
+
+*Returns*: If has_value() is true, expected<T, G>(); otherwise, anexpected<T, G> object whose *has_val* member is false and *unex* member is direct-non-list-initialized withinvoke(std::forward<F>(f), error())[.](#25.sentence-1)
+
+[ð](#lib:transform_error,expected%3cvoid%3e_)
+
+`template<class F> constexpr auto transform_error(F&& f) &&;
+template<class F> constexpr auto transform_error(F&& f) const &&;
+`
+
+[26](#26)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10297)
+
+Let G beremove_cv_t<invoke_result_t<F, decltype(std::move(error()))>>[.](#26.sentence-1)
+
+[27](#27)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10301)
+
+*Mandates*: G is a valid template argument
+for unexpected ([[expected.un.general]](expected.un.general "22.8.3.1 General")) and the declarationG g(invoke(std::forward<F>(f), std::move(error()))); is well-formed[.](#27.sentence-1)
+
+[28](#28)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10310)
+
+*Returns*: If has_value() is true, expected<T, G>(); otherwise, anexpected<T, G> object whose *has_val* member is false and *unex* member is direct-non-list-initialized withinvoke(std::forward<F>(f), std::move(error()))[.](#28.sentence-1)
--- a/cppdraft/expected/void/obs.md
+++ b/cppdraft/expected/void/obs.md
@@ -0,0 +1,136 @@
+[expected.void.obs]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.obs)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#obs)
+
+#### 22.8.7.6 Observers [expected.void.obs]
+
+[ð](#lib:operator_bool,expected%3cvoid%3e)
+
+`constexpr explicit operator bool() const noexcept;
+constexpr bool has_value() const noexcept;
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9954)
+
+*Returns*: *has_val*[.](#1.sentence-1)
+
+[ð](#lib:operator*,expected%3cvoid%3e)
+
+`constexpr void operator*() const noexcept;
+`
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9965)
+
+*Hardened preconditions*: has_value() is true[.](#2.sentence-1)
+
+[ð](#lib:value,expected%3cvoid%3e)
+
+`constexpr void value() const &;
+`
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9976)
+
+*Mandates*: is_copy_constructible_v<E> is true[.](#3.sentence-1)
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9980)
+
+*Throws*: bad_expected_access(error()) if has_value() is false[.](#4.sentence-1)
+
+[ð](#lib:value,expected%3cvoid%3e_)
+
+`constexpr void value() &&;
+`
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9991)
+
+*Mandates*: is_copy_constructible_v<E> is true andis_move_constructible_v<E> is true[.](#5.sentence-1)
+
+[6](#6)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9996)
+
+*Throws*: bad_expected_access(std::move(error())) if has_value() is false[.](#6.sentence-1)
+
+[ð](#lib:error,expected%3cvoid%3e)
+
+`constexpr const E& error() const & noexcept;
+constexpr E& error() & noexcept;
+`
+
+[7](#7)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10009)
+
+*Hardened preconditions*: has_value() is false[.](#7.sentence-1)
+
+[8](#8)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10013)
+
+*Returns*: *unex*[.](#8.sentence-1)
+
+[ð](#lib:error,expected%3cvoid%3e_)
+
+`constexpr E&& error() && noexcept;
+constexpr const E&& error() const && noexcept;
+`
+
+[9](#9)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10025)
+
+*Hardened preconditions*: has_value() is false[.](#9.sentence-1)
+
+[10](#10)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10029)
+
+*Returns*: std::move(*unex*)[.](#10.sentence-1)
+
+[ð](#lib:error_or,expected%3cvoid%3e)
+
+`template<class G = E> constexpr E error_or(G&& e) const &;
+`
+
+[11](#11)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10040)
+
+*Mandates*: is_copy_constructible_v<E> is true andis_convertible_v<G, E> is true[.](#11.sentence-1)
+
+[12](#12)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10045)
+
+*Returns*: std::forward<G>(e) if has_value() is true,error() otherwise[.](#12.sentence-1)
+
+[ð](#lib:error_or,expected%3cvoid%3e_)
+
+`template<class G = E> constexpr E error_or(G&& e) &&;
+`
+
+[13](#13)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10057)
+
+*Mandates*: is_move_constructible_v<E> is true andis_convertible_v<G, E> is true[.](#13.sentence-1)
+
+[14](#14)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L10062)
+
+*Returns*: std::forward<G>(e) if has_value() is true,std::move(error()) otherwise[.](#14.sentence-1)
--- a/cppdraft/expected/void/swap.md
+++ b/cppdraft/expected/void/swap.md
@@ -0,0 +1,60 @@
+[expected.void.swap]
+
+# 22 General utilities library [[utilities]](./#utilities)
+
+## 22.8 Expected objects [[expected]](expected#void.swap)
+
+### 22.8.7 Partial specialization of expected for void types [[expected.void]](expected.void#swap)
+
+#### 22.8.7.5 Swap [expected.void.swap]
+
+[ð](#lib:swap,expected%3cvoid%3e)
+
+`constexpr void swap(expected& rhs) noexcept(see below);
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9893)
+
+*Constraints*: is_swappable_v<E> is true andis_move_constructible_v<E> is true[.](#1.sentence-1)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9898)
+
+*Effects*: See Table [73](#tab:expected.void.swap "Table 73: swap(expected&amp;) effects")[.](#2.sentence-1)
+
+Table [73](#tab:expected.void.swap) — swap(expected&) effects [[tab:expected.void.swap]](./tab:expected.void.swap)  
+
+| [ð](#tab:expected.void.swap-row-1) | **this->has_value()** | **!this->has_value()** |
+| --- | --- | --- |
+| [ð](#tab:expected.void.swap-row-2)<br>**rhs.has_value()** | no effects | calls rhs.swap(*this) |
+| [ð](#tab:expected.void.swap-row-3)<br>**!rhs.has_value()** | *see below* | equivalent to: using std::swap; swap(*unex*, rhs.*unex*); |
+
+For the case where rhs.has_value() is false andthis->has_value() is true, equivalent to:construct_at(addressof(*unex*), std::move(rhs.*unex*));
+destroy_at(addressof(rhs.*unex*));*has_val* = false;
+rhs.*has_val* = true;
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9923)
+
+*Throws*: Any exception thrown by the expressions in the *Effects*[.](#3.sentence-1)
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9927)
+
+*Remarks*: The exception specification is equivalent tois_nothrow_move_constructible_v<E> && is_nothrow_swappable_v<E>[.](#4.sentence-1)
+
+[ð](#lib:swap,expected%3cvoid%3e_)
+
+`friend constexpr void swap(expected& x, expected& y) noexcept(noexcept(x.swap(y)));
+`
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L9939)
+
+*Effects*: Equivalent to x.swap(y)[.](#5.sentence-1)