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//--------------------------------------------------------------------------------------------------
#include <iostream>
#include <iomanip>

//--------------------------------------------------------------------------------------------------
namespace Mpl
{
    

    template<class Base, class Derived>
    struct IsDerived
    {
    private:
        struct YesType { char a[1]; };
        struct NoType  { char a[10]; };

        static YesType    deduce(Base*);
        static NoType   deduce(...);        

    public:
        enum
        {
            value = (sizeof(deduce(static_cast<Derived*>(NULL))) == sizeof(YesType))
        };
    };
}

template<class B, class D>
bool isDerived(D const&)
{
    return (Mpl::IsDerived<B, D>::value != 0)? true : false;
}


struct A {};
struct B {};
struct C : A {};

//--------------------------------------------------------------------------------------------------
//
//
int main(int argc, char const* const argv[])
{
    B b;
    C c;

    std::cout << std::boolalpha;
    std::cout << isDerived<A>(b) << std::endl;
    std::cout << isDerived<A>(c) << std::endl;
    return 0;
}
//--------------------------------------------------------------------------------------------------