How to determine if a type is derived from a template class?
How can I determine if a type is derived from a template class? In particular, I need to determine if a template parameter has std::basic_ostream as a base class.
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Might something like Boost's is_instance_of be what you are after?
http://www.boost.org/doc/libs/1_46_1/boost/lambda/detail/is_instance_of.hpp
Here is the short version for 1-argument templates:
#include#include template class F> struct conversion_tester { template conversion_tester (const F &); }; template class To> struct is_instance_of { static const bool value = std::is_convertible struct foo {}; template struct bar {}; int main() { std::cout << is_instance_of Unfortunately, if you try to extend this to variadic templates, with current GCC (4.6.0) it will produce an error message. This SO answer implies that this is currently a problem of GCC and that the variadic template version is supposed to work according to the standard.
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