Using a namespace in place of a static class in C++?

Question

Is it good or okay practice to use a namespace as a static class? For example:

namespace MyStaticFunctions {
    void doSomething();
}

Vers

Answer 1

In C++, you are actually encouraged at the language level to use a namespace rather than a class containing only static methods because of Koenig's lookup (aka Argument Dependent Lookup).

Example:

namespace geometry {
    struct Point { int x, y; };

    double distance_from_center(Point const& p) {
        return sqrt(p.x * p.x + p.y + p.y);
    }
} // namespace geometry

int main() {
    geometry::Point const p{3, 4}; // must qualify

    std::cout << distance_from_center(p) << "\n"; // not qualified
}

If distance_from_center is written as a static method in a class, then you need to explicitly qualify it each time.