std:: swap (std::pair)
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Defined in header
<utility>
|
||
| (1) | ||
|
template
<
class
T1,
class
T2
>
void
swap
(
std::
pair
<
T1,T2
>
&
x,
std::
pair
<
T1,T2
>
&
y
)
|
(since C++11)
(until C++20) |
|
|
template
<
class
T1,
class
T2
>
constexpr
void
swap
(
std::
pair
<
T1,T2
>
&
x,
std::
pair
<
T1,T2
>
&
y
)
|
(since C++20) | |
|
template
<
class
T1,
class
T2
>
constexpr
void
swap
(
const
std::
pair
<
T1,T2
>
&
x,
const
std::
pair
<
T1,T2
>
&
y
)
|
(2) | (since C++23) |
Swaps the contents of
x
and
y
. Equivalent to
x.
swap
(
y
)
.
|
1)
This overload participates in overload resolution only if
std::
is_swappable_v
<
first_type
>
&&
std::
is_swappable_v
<
second_type
>
is
true
.
2)
This overload participates in overload resolution only if
std::
is_swappable_v
<
const
first_type
>
&&
std::
is_swappable_v
<
const
second_type
>
is
true
.
|
(since C++17) |
Parameters
| x, y | - | pairs whose contents to swap |
Return value
(none)
Exceptions
Example
#include <iostream> #include <utility> int main() { auto p1 = std::make_pair(10, 3.14); auto p2 = std::pair(12, 1.23); // CTAD, since C++17 auto print_p1_p2 = [&](auto msg) { std::cout << msg << "p1 = {" << std::get<0>(p1) << ", " << std::get<1>(p1) << "}, " << "p2 = {" << std::get<0>(p2) << ", " << std::get<1>(p2) << "}\n"; }; print_p1_p2("Before p1.swap(p2): "); p1.swap(p2); print_p1_p2("After p1.swap(p2): "); std::swap(p1, p2); print_p1_p2("After swap(p1, p2): "); }
Output:
Before p1.swap(p2): p1 = {10, 3.14}, p2 = {12, 1.23}
After p1.swap(p2): p1 = {12, 1.23}, p2 = {10, 3.14}
After swap(p1, p2): p1 = {10, 3.14}, p2 = {12, 1.23}
See also
|
swaps the values of two objects
(function template) |
|
|
(C++11)
|
specializes the
std::swap
algorithm
(function template) |