c++ - How to test casting time? -

in assignment, have been asked create own static_cast , dynamic_cast using templates specialization. how test static casts done compile-time , dynamic casts on run-time?

template<typename dst, typename src> static dst my_static_cast(src src);  template<typename dst, typename src> static dst my_dynamic_cast(src src); 

not full answer consider this:

class d { public:     virtual ~d(){} }; class : public d{};  class b{}; 

now dynamic_cast<b*>(new a()) compiles ok (and returns 0) static_cast<b*>(new a()) results in compilation error. i'm sure can sfinae make appropriate test.

of course, test assumes need differentiate between 100% standard-compliant static_cast , 100% standard-compliant dynamic_cast. detecting bugs in implementation additional tests needed.

edit: cannot test automatically. casts require runtime arguments , cannot tested @ compile time. and, @ runtime, difference between compile-time calculated thing , runtime-calculated thing performance. wouldn't recommend testing "well, runtime casts can't fast". isn't reliable.