Re: [Boost-users] How to test if a type is of some form?

2008/9/24 Peng Yu

Hi,

I want to test if template argument is of some form like in the following code. I could define some helper class to do such test. But I'm wondering if there is any easy to do it with boost? The type_traits's is_same does not work in this case. I'm wondering if there could be some generalization of it.

template <T> void f() { //For example, I want to test if T is of the // form of std::complex<S>

}

Thanks, Peng

Take a look at boost::lambda::is_instance_of (boost/lambda/detail/is_instance_of.hpp). template <class T> void f() { if (boost::lambda::is_instance_of::value) std::cout << "T is an instance of std::complex" << std::endl; else std::cout << "T is not an instance of std::complex" << std::endl; } Note: code resides in the detail directory meaning that it's not part of the public interface. Roman Perepelitsa.