std::signed_integral(3)

💖 NAME 💖

hey bestie, this is the std::signed_integral(3) page from the C++ Standard Libary — yep, that spelling is in the header and we’re keeping it, periodt. 💅

std::signed_integral - std::signed_integral — yes, the name is literally the same as the thing, and honestly? iconic minimalism. 🎀

✨ Synopsis ✨

Defined in header <concepts>.

template< class T >

(since C++20)

concept signed_integral = std::integral<T> && std::is_signed_v<T>;

The concept signed_integral<T> is satisfied if and only if T is an integral type and std::is_signed_v<T> is true. That’s the whole vibe check, no cap. ✨

🧠 Notes 🧠

Heads up, bestie: signed_integral<T> may be satisfied by a type that is not a signed integer type — for example, char (on a system where char is signed). So yeah, the plot twist is real. 😭

🌈 Example 🌈

       // Run this code

        #include <concepts>
        #include <iostream>
        #include <string_view>

        void test(std::signed_integral auto x, std::string_view text = "")
        {
            std::cout << text << " (" + (text == "") << x << ") is a signed
       integral\n";
        }

        void test(std::unsigned_integral auto x, std::string_view text = "")
        {
            std::cout << text << " (" + (text == "") << x << ") is an unsigned
       integral\n";
        }

        void test(auto x, std::string_view text = "")
        {
            std::cout << text << " (" + (text == "") << x << ") is non-
       integral\n";
        }

        int main()
        {
            test(42);               // signed
            test(0xFULL, "0xFULL"); // unsigned
            test('A');              // platform-dependent
            test(true, "true");     // unsigned
            test(4e-2, "4e-2");     // non-integral (hex-float)
            test("∫∫");             // non-integral
        }

Possible output:

        (42) is a signed integral
        0xFULL (15) is an unsigned integral
        (A) is a signed integral
        true (1) is an unsigned integral
        4e-2 (0.04) is non-integral
        (∫∫) is non-integral

👀 See also 👀

• is_integral — checks if a type is an integral type (C++11) (class template)
• is_signed — checks if a type is a signed arithmetic type (C++11) (class template)

mwah 💋 — source: http://cppreference.com, version/date: 2024.06.10, page: std::signed_integral(3). bye bestie, go slay your type traits! 🫶