std::{{{1}}}::operator=

 

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{{{1}}}& operator=( const {{{1}}}& other );	(1)	(since {std}) (implicitly declared)
{{{1}}}& operator=( {{{1}}}&& other );	(2)	(since C++11) (implicitly declared)

Replaces the contents of the container adaptor with the contents of given argument.

1) Copy assignment operator. Replaces the contents with a copy of the contents of other. Effectively calls c = other.c; comp = other.comp;.

2) Move assignment operator. Replaces the contents with those of other using move semantics. Effectively calls c = std::move(other.c); comp = std::move(other.comp);.

Parameters

other

-

another container adaptor to be used as source

Return value

*this

Complexity

1,2) Equivalent to that of operator= of the underlying container.

Example

Run this code

#include <>
#include <initializer_list>
#include <print>
#include <utility>
 
int main()
{
    std::<int, int> x{{1, 1}, {2, 2}, {3, 3}}, y, z;
    const auto w = {std::pair<const int, int>{4, 4}, {5, 5}, {6, 6}, {7, 7}};
 
    std::println("Initially:");
    std::println("x = {}", x);
    std::println("y = {}", y);
    std::println("z = {}", z);
 
    y = x; // overload (1)
    std::println("Copy assignment copies data from x to y:");
    std::println("x = {}", x);
    std::println("y = {}", y);
 
    z = std::move(x); // overload (2)
    std::println("Move assignment moves data from x to z, modifying both x and z:");
    std::println("x = {}", x);
    std::println("z = {}", z);
 
    z = w; // overload (3)
    std::println("Assignment of initializer_list w to z:");
    std::println("w = {}", w);
    std::println("z = {}", z);
}

Output:

Initially:
x = {1: 1, 2: 2, 3: 3}
y = {}
z = {}
Copy assignment copies data from x to y:
x = {1: 1, 2: 2, 3: 3}
y = {1: 1, 2: 2, 3: 3}
Move assignment moves data from x to z, modifying both x and z:
x = {}
z = {1: 1, 2: 2, 3: 3}
Assignment of initializer_list w to z:
w = {4: 4, 5: 5, 6: 6, 7: 7}
z = {4: 4, 5: 5, 6: 6, 7: 7}

See also

(constructor)

constructs the (public member function of std::{{{1}}})