std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::operator= - cppreference.com (original) (raw)
| flat_map& operator=( const flat_map& other ); | (1) | (since C++23) (implicitly declared) |
|---|---|---|
| flat_map& operator=( flat_map&& other ); | (2) | (since C++23) (implicitly declared) |
| flat_map& operator=( std::initializer_list<value_type> ilist ); | (3) | (since C++23) |
Replaces the contents of the container adaptor with the contents of given argument.
Copy assignment operator. Replaces the contents with a copy of the contents of other. Effectively calls c = other.c; comp = other.comp;.
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);.
Replaces the contents with those identified by initializer list ilist.
[edit] Parameters
| other | - | another container adaptor to be used as source |
|---|---|---|
| ilist | - | initializer list to be used as source |
[edit] Return value
*this
[edit] Complexity
1,2) Equivalent to that of operator= of the underlying container.
- Linear in the size of *this and ilist.
[edit] Example
#include #include #include #include int main() { std::flat_map<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}