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+[iterator.cust]
+
+# 24 Iterators library [[iterators]](./#iterators)
+
+## 24.3 Iterator requirements [[iterator.requirements]](iterator.requirements#iterator.cust)
+
+### 24.3.3 Customization point objects [iterator.cust]
+
+#### [24.3.3.1](#move) ranges::iter_move [[iterator.cust.move]](iterator.cust.move)
+
+[1](#move-1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1149)
+
+The name ranges::iter_move denotes
+a customization point object ([[customization.point.object]](customization.point.object "16.3.3.3.5 Customization Point Object types"))[.](#move-1.sentence-1)
+
+The expression ranges::iter_move(E) for a subexpression E is
+expression-equivalent to:
+
+- [(1.1)](#move-1.1)
+
+  iter_move(E), ifE has class or enumeration type anditer_move(E) is a well-formed expression when treated as an unevaluated operand,
+where the meaning of iter_move is established as-if by performing
+argument-dependent lookup only ([[basic.lookup.argdep]](basic.lookup.argdep "6.5.4 Argument-dependent name lookup"))[.](#move-1.1.sentence-1)
+
+- [(1.2)](#move-1.2)
+
+  Otherwise, if the expression *E is well-formed:
+  * [(1.2.1)](#move-1.2.1)
+
+if *E is an lvalue, std::move(*E);
+
+  * [(1.2.2)](#move-1.2.2)
+
+otherwise, *E[.](#move-1.2.sentence-1)
+
+- [(1.3)](#move-1.3)
+
+  Otherwise, ranges::iter_move(E) is ill-formed[.](#move-1.3.sentence-1)
+  [*Note [1](#move-note-1)*:
+  This case can result in substitution failure when ranges::iter_move(E) appears in the immediate context of a template instantiation[.](#move-1.3.sentence-2)
+ â *end note*]
+
+[2](#move-2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1175)
+
+If ranges::iter_move(E) is not equal to *E,
+the program is ill-formed, no diagnostic required[.](#move-2.sentence-1)
+
+#### [24.3.3.2](#swap) ranges::iter_swap [[iterator.cust.swap]](iterator.cust.swap)
+
+[1](#swap-1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1182)
+
+The name ranges::iter_swap denotes
+a customization point object ([[customization.point.object]](customization.point.object "16.3.3.3.5 Customization Point Object types"))
+that exchanges the values ([[concept.swappable]](concept.swappable "18.4.9 Concept swappable")) denoted by its
+arguments[.](#swap-1.sentence-1)
+
+[2](#swap-2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1188)
+
+Let *iter-exchange-move* be the exposition-only function template:
+
+[ð](#swap-itemdecl:1)
+
+`template<class X, class Y>
+  constexpr iter_value_t<X> iter-exchange-move(X&& x, Y&& y)
+    noexcept(noexcept(iter_value_t<X>(iter_move(x))) &&
+             noexcept(*x = iter_move(y)));
+`
+
+[3](#swap-3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1198)
+
+*Effects*: Equivalent to:iter_value_t<X> old_value(iter_move(x));*x = iter_move(y);return old_value;
+
+[4](#swap-4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iterators.tex#L1208)
+
+The expression ranges::iter_swap(E1, E2) for subexpressionsE1 and E2 is expression-equivalent to:
+
+- [(4.1)](#swap-4.1)
+
+  (void)iter_swap(E1, E2), if eitherE1 or E2 has class or enumeration type anditer_swap(E1, E2) is a well-formed expression
+with overload resolution performed in a context that includes the declarationtemplate<class I1, class I2>void iter_swap(I1, I2) = delete; and does not include a declaration of ranges::iter_swap[.](#swap-4.1.sentence-1)
+  If the function selected by overload resolution does not exchange the values
+denoted by E1 and E2,
+the program is ill-formed, no diagnostic required[.](#swap-4.1.sentence-2)
+  [*Note [1](#swap-note-1)*:
+  This precludes calling unconstrained std::iter_swap[.](#swap-4.1.sentence-3)
+  When the deleted
+overload is viable, program-defined overloads need to be more
+specialized ([[temp.func.order]](temp.func.order "13.7.7.3 Partial ordering of function templates")) to be selected[.](#swap-4.1.sentence-4)
+ â *end note*]
+
+- [(4.2)](#swap-4.2)
+
+  Otherwise, if the types of E1 and E2 each model[indirectly_readable](iterator.concept.readable#concept:indirectly_readable "24.3.4.2 Concept indirectly_readable [iterator.concept.readable]"), and if the reference types of E1 and E2 model [swappable_with](concept.swappable#concept:swappable_with "18.4.9 Concept swappable [concept.swappable]") ([[concept.swappable]](concept.swappable "18.4.9 Concept swappable")),
+then ranges::swap(*E1, *E2)[.](#swap-4.2.sentence-1)
+
+- [(4.3)](#swap-4.3)
+
+  Otherwise, if the types T1 and T2 of E1 andE2 model [indirectly_movable_storable](alg.req.ind.move#concept:indirectly_movable_storable "24.3.7.2 Concept indirectly_movable [alg.req.ind.move]")<T1, T2> and[indirectly_movable_storable](alg.req.ind.move#concept:indirectly_movable_storable "24.3.7.2 Concept indirectly_movable [alg.req.ind.move]")<T2, T1>, then(void)(*E1 = *iter-exchange-move*(E2, E1)),
+except that E1 is evaluated only once[.](#swap-4.3.sentence-1)
+
+- [(4.4)](#swap-4.4)
+
+  Otherwise, ranges::iter_swap(E1, E2) is ill-formed[.](#swap-4.4.sentence-1)
+  [*Note [2](#swap-note-2)*:
+  This case can result in substitution failure when ranges::iter_swap(E1, E2) appears in the immediate context of a template instantiation[.](#swap-4.4.sentence-2)
+ â *end note*]