std::integral(3)

NAME
std::integral - std::integral

Synopsis
   Defined in header <concepts>
   template< class T > (since C++20)
   concept integral = std::is_integral_v<T>;
   The concept integral<T> is satisfied if and only if T is an integral type.

Example
// Run this code
 #include <concepts>
 #include <iostream>
 void print(std::integral auto i)
 {
     std::cout << "Integral: " << i << '\n';
 }
 void print(auto x)
 {
     std::cout << "Non-integral: " << x << '\n';
 }
 int main()
 {
     std::cout << std::boolalpha;
     static_assert(std::integral<bool>);
     print(true);
     static_assert(std::integral<char>);
     print('o');
     static_assert(std::integral<int>);
     print(007);
     static_assert( ! std::integral<double> );
     print(2e2);
     static_assert( ! std::integral<decltype("")> );
     print("∫∫∫");
 }

Output:
 Integral: true
 Integral: o
 Integral: 7
 Non-integral: 200
 Non-integral: ∫∫∫

See also
   is_integral checks if a type is an integral type
   (C++11) (class template)