'Helper' functions in C++

Question

While refactoring some old code I have stripped out a number of public methods that should actually of been statics as they a) don't operate on any member data or call any other member functions and b) because they might prove useful elsewhere.

This led me to think about the best way to group 'helper' functions together. The Java/C# way would be to use a class of static functions with a private constructor, e.g.:

class Helper  
{  
private:  
  Helper() { }
public:  
  static int HelperFunc1();  
  static int HelperFunc2();  
};

However, being C++ you could also use a namespace:

namespace Helper  
{  
  int HelperFunc1();  
  int HelperFunc2();  
}

In most cases I think I would prefer the namespace approach but I wanted to know what the pros and cons of each approach are. If used the class approach for example, would there be any overheads?

Answer 1

Namespaces offer the additional advantage of Koenig lookup. Using helper classes may make your code more verbose - you usually need to include the helper class name in the call.

Another benefit to namespaces is in readability later on. With classes, you need to include words like "Helper" to remind you later that the particular class isn't used to create objects

In practice, there's no overhead in either. After compilation, only the name mangling used differs.