std::flat_m...p::operator=(3)

Okay bestie, this is std::flat_m...p::operator=(3) from the C++ Standard Libary — and yes, it’s literally the assignment-operator page for std::flat_multimap 💅✨

💖 NAME 💖

std::flat_multimap::operator= — std::flat_multimap::operator=

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✨ Synopsis ✨

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

This operator replaces the contents of the container adaptor with the contents of the given argument. Periodt 🫶

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.

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🎀 Parameters 🎀

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

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🦋 Return value 🦋

*this — she returns herself, no cap 💅

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🌸 Complexity 🌸

1. 1,2) — Equivalent to that of operator= of the underlying container.
2. 3) — Linear in the size of *this and ilist.

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💖 Example 💖

The page says // Run this code before the snippet:

#include <flat_map>
#include <initializer_list>
#include <print>
#include <utility>

int main()
{
    std::flat_multimap<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}

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👑 See also 👑

• constructor — constructs the flat_multimap (public member function)
• replace — replaces the underlying containers (public member function)

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Source: http://cppreference.com · Version/date: 2024.06.10 · page: std::flat_m...p::operator=(3) — byeee bestie, go assign something iconic 🫶💖🎀