std::flat_set<Key,Compare,KeyContainer>::operator=

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Containers library

Sequence

array (C++11)

vector

vector<bool>

inplace_vector (C++26)

deque

forward_list (C++11)

list

Associative

set

multiset

map

multimap

Unordered associative

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

Adaptors

stack

queue

priority_queue

flat_set (C++23)

flat_multiset (C++23)

flat_map (C++23)

flat_multimap (C++23)

Views

span (C++20)

mdspan (C++23)

Tables

Iterator invalidation

Member function table

Non-member function table

 

std::flat_set

Member types

Member functions

flat_set::flat_set flat_set::operator= Iterators flat_set::beginflat_set::cbegin flat_set::endflat_set::cend flat_set::rbeginflat_set::crbegin flat_set::rendflat_set::crend Capacity flat_set::size flat_set::max_size flat_set::empty Observers flat_set::key_comp flat_set::value_comp      Modifiers flat_set::clear flat_set::insert flat_set::insert_range flat_set::emplace flat_set::emplace_hint flat_set::erase flat_set::swap flat_set::extract flat_set::replace Lookup flat_set::count flat_set::find flat_set::contains flat_set::equal_range flat_set::lower_bound flat_set::upper_bound Non-member functions operator==operator<=> swap(std::flat_set) erase_if(std::flat_set)

Helper classes

uses_allocator<std::flat_set>

Tags

sorted_unique      sorted_unique_t

Deduction guides

 

flat_set& operator=( const flat_set& other );	(1)	(since C++23) (implicitly declared)
flat_set& operator=( flat_set&& other );	(2)	(since C++23) (implicitly declared)
flat_set& operator=( std::initializer_list<key_type> ilist );	(3)	(since C++23)

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);.

3) Replaces the contents with those identified by initializer list ilist.

Parameters

other	-	another container adaptor to be used as source
ilist	-	initializer list to be used as source

Return value

*this

Complexity

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

3) Linear in the size of *this and ilist.

Example

Run this code

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

See also

(constructor)	constructs the flat_set (public member function)
replace	replaces the underlying container (public member function)