Combining Concepts with Logical Operators

Yes, you can combine multiple concepts using logical operators like && (and) and || (or) in a requires clause. This allows you to specify more complex constraints on template parameters. Here's an example:

1#include <concepts>
2#include <string>
3
4template <typename T>
5requires std::integral<T>
6  || std::floating_point<T>
7T add(T a, T b) {
8  return a + b;
9}
10
11int main() {
12  // Valid, int is an integral type
13  int intResult = add(5, 3);
14
15  // Valid, double is a floating-point type
16  double doubleResult = add(2.5, 1.7);
17
18  // Invalid
19  std::string strResult = add("Hello", "World");
20}

1error: 'add': no matching overloaded function found
2could be 'T add(T,T)'
3the associated constraints are not satisfied
4the concept 'std::integral<const char*>' evaluated to false

In this example, the add function template is constrained to accept types that are either integral or floating-point using the || operator in the requires clause. This allows the function to be called with both int and double arguments, but not with std::string.