std::flat_m...:value_comp(3)

okay so bestie, you’re on the std::flat_m...:value_comp(3) page from the C++ Standard Libary manual — yes, that’s the exact spelling, no cap — and it’s literally all about std::flat_multiset::value_comp. it’s giving “tiny but important member function” energy 💅✨

✨ NAME ✨

std::flat_multiset::value_comp — std::flat_multiset::value_comp

🌸 Synopsis 🌸

std::flat_multiset::value_compare value_comp() const;  (since C++23)

so this one returns the function object that compares the values — and it is the same as key_comp. periodt. 🎀

🎀 Parameters 🎀

(none) — literally no parameters, bestie. zero. nada. 🫶

💖 Return value 💖

The value comparison function object. that’s the whole vibe. 💅

⚡ Complexity ⚡

Constant. ⭐

🧚 Example 🧚

okay so here’s the example, run this code:

// Run this code

#include <iostream>
#include <flat_set>
#include <utility>

// Example module 97 key compare function
struct ModCmp
{
    bool operator()(int lhs, int rhs) const
    {
        return (lhs % 97) < (rhs % 97);
    }
};

int main()
{
    std::flat_multiset<int, ModCmp> cont{1, 2, 3, 4, 5};

    // Same behaviour as key_comp()
    auto comp_func = cont.value_comp();

    for (const int val{100}; const int key : cont)
    {
        const bool before = comp_func(key, val);
        const bool after = comp_func(val, key);

        std::cout << "Key (" << key << ") ";
        if (!before && !after)
            std::cout << "equivalent to key (" << val << ")\n";
        else if (before)
            std::cout << "goes before key (" << val << ")\n";
        else if (after)
            std::cout << "goes after key (" << val << ")\n";
        else
            std::unreachable();
    }
}

💬 Output 💬

and the output is giving:

Key (1) goes before key (100)
Key (2) goes before key (100)
Key (3) equivalent to key (100)
Key (4) goes after key (100)
Key (5) goes after key (100)

🔗 See also 🔗

• key_comp — returns the function that compares keys (public member function)

mwah 💋 — this page came from http://cppreference.com, version/date 2024.06.10, on std::flat_m...:value_comp(3). catch you later, bestie 🫶✨