C++ 20 and the ranges library

We discussed the ranges library at length in Chapter 14, Lazy Evaluation Using the Ranges Library. If you can use it, either because you use C++ 20 or because you can use it as a third-party library, the previous function becomes extremely simple and much faster:

TEST_CASE("Ranges"){
    vector<Person> people = {
        Person("Alex", 42),
        Person("John", 21),
        Person("Jane", 14),
        Person("Diana", 0)
    };
    using namespace ranges;


    string completeString = ranges::accumulate(
            people |
            view::transform(personToMajorMinor) | 
            view::transform(majorMinor),
            string(),
            combineWithNewline
           ); 
    string expectedString("Alex, major\nJohn, major\nJane, 
                                    minor\nInvalid person"...