std::strict_weak_order(3)

💖 NAME 💖

okay so welcome to std::strict_weak_order(3), the C++ Standard Libary page that's about to make strict weak ordering make sense, bestie. The name is literally std::strict_weak_order — std::strict_weak_order. iconic, no notes. 💅

✨ Synopsis ✨

Defined in header <concepts>:

template< class R, class T, class U >                (since C++20)
concept strict_weak_order = std::relation<R, T, U>;

The concept strict_weak_order<R, T, U> specifies that the relation R imposes a strict weak ordering on its arguments. that's the whole vibe check. 🦋

🧠 Semantic requirements 🧠

A relation r is a strict weak ordering if:

• it is irreflexive: for all x, r(x, x) is false;
• it is transitive: for all a, b and c, if r(a, b) and r(b, c) are both true then r(a, c) is true;
• let e(a, b) be !r(a, b) && !r(b, a), then e is transitive: e(a, b) && e(b, c) implies e(a, c).

Under these conditions, it can be shown that e is an equivalence relation, and r induces a strict total ordering on the equivalence classes determined by e. like wow, math ate. 😭✨

📝 Notes 📝

The distinction between relation and strict_weak_order is purely semantic. lowkey important, highkey just semantics. 🫶

👀 See also 👀

• LessThanComparable

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mwah 💋 — source: cppreference.com, version/date 2024.06.10, page std::strict_weak_order(3). bye bestie, go slay your comparators 🌸👑