"Suki" <suryakiran.gullapalli@gmail.com> 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 <boost/mpl/or.hpp> #include <boost/mpl/assert.hpp> #include <boost/type_traits/is_same.hpp> template <class T> struct myClass { BOOST_MPL_ASSERT((boost::mpl::or_< boost::is_same<T,int> , boost::is_same<T,float> , boost::is_same<T,char> >)); ... // 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