Re: [Boost-users] Templates Question

"Suki" writes:

Hi, I'm writing a templated class, and i dont want to use the class otherthan for some predetermined types, say, int, double etc.

This class has no meaning for typenames other than those few.

========================= template <class T> myClass {....} ;

myClass<int> intClass ; myClass<float> floatClass ; myClass<char> charClass ; =========================

The compiler should not complain for the first 2 instantiations, but should bail out at the 3rd instantiation (charClass). Is there any way i can achieve this, using standard c++ or boost.

Declarative way: template <class T> struct myClass_impl { ... }; template <class T> struct myClass; template<> myClass<int> : myClass_impl<int> {}; template<> myClass<float> : myClass_impl<float> {}; template<> myClass<char> : myClass_impl<char> {}; Imperative way: #include #include #include template <class T> struct myClass { BOOST_MPL_ASSERT((boost::mpl::or_< boost::is_same , boost::is_same , boost::is_same >)); ... // your class implementation here. };

to summarize my question, is there any way i can restrict the compiler to accept only few type names for my templated class (i.e., using standard c++ or boost)

HTH, -- Dave Abrahams Boost Consulting www.boost-consulting.com