[Boost-users] Which is preferred? Static assertions with type traits or concept_check?

From: Benjamin Lau (blwy10v_at_[hidden])
Date: 2007-04-02 07:20:54

Hi all,

I'm writing a template class and I have several requirements on the
type parameters. A lot of it has to do with the inter-convertibility
of the types. I have 2 options to choose from as to how I can check
for these convertibility requirements: static assertions with the type
traits selector is_convertible, or using concept_check to check if the
assignment operation is defined for the types. Even though the former
leads to shorter code, the latter works just as well as I already have
concepts modeled for these types, so I could just dump the
inter-convertibility checks inside as well without much hassle.

In summary, I either choose this:

BOOST_STATIC_ASSERT((boost::is_convertible<T1, T2>::value));

or this:

template<class T1, class T2> class Concept
{
public:
        void constraints()
        {
                // insert other constraints

                a = b;
                b = a;
        }
        T1 a;
        T2 b;
};

Thanks a lot, and have a good day
Benjamin Lau