[tuple.swap]

# 22 General utilities library [[utilities]](./#utilities)

## 22.4 Tuples [[tuple]](tuple#swap)

### 22.4.4 Class template tuple [[tuple.tuple]](tuple.tuple#tuple.swap)

#### 22.4.4.4 swap [tuple.swap]

[ð](#lib:swap,tuple)

`constexpr void swap(tuple& rhs) noexcept(see below);
constexpr void swap(const tuple& rhs) const noexcept(see below);
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2532)

Let i be in the range [0, sizeof...(Types)) in order[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2535)

*Mandates*: 

- [(2.1)](#2.1)

  For the first overload,(is_swappable_v<Types> && ...) is true[.](#2.1.sentence-1)

- [(2.2)](#2.2)

  For the second overload,(is_swappable_v<const Types> && ...) is true[.](#2.2.sentence-1)

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2546)

*Preconditions*: For all i, get<i>(*this) is swappable with ([[swappable.requirements]](swappable.requirements "16.4.4.3 Swappable requirements")) get<i>(rhs)[.](#3.sentence-1)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2550)

*Effects*: For each i, calls swap for get<i>(*this) and get<i>(rhs)[.](#4.sentence-1)

[5](#5)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2554)

*Throws*: Nothing unless one of the element-wise swap calls throws an exception[.](#5.sentence-1)

[6](#6)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L2558)

*Remarks*: The exception specification is equivalent to

- [(6.1)](#6.1)

(is_nothrow_swappable_v<Types> && ...) for the first overload and

- [(6.2)](#6.2)

(is_nothrow_swappable_v<const Types> && ...) for the second overload[.](#6.sentence-1)
