meta-programming: inherit from every class in a boost mpl::vector
I wish to inherit from a set of classes contained in a boost mpl::vector. Is this possible?
Specifically, I wish to extend test
for arbitrary many template parameters, passed as a mpl::vector.
template<class T>
struct Slice
{
public:
virtual void foo(T v) const = 0;
};
struct A{};
struct B{};
template <class T1, class T2>
struct test : public Slice<T1>, public Slice<T2>
{
void foo(T1 a) const {std::cout<<"A"<<std::endl;}
void foo(T2 b) const {std::cout<<"B"<<std::endl;}
};
If I know there are only two parameters then I can simply write:
template <class mpl_vector_t >
struct test : public Slice<typename mpl::at<mpl_vector_t,mpl::int_<0> >::type >,
public Slice<typename mpl::at<mpl_vector_t,mpl::int_<1> >::type >
{
typedef typename mpl::at<mpl_vector_t,mpl::int_<0> >::type T1;
typedef typename mpl::at<mpl_vector_t,mpl::int_<1> >::type T2;
void foo(T1 a) const {std::cout<<"A"<<std::endl;}
void foo(T2 b) const {std::cout<<"B"<<std::endl;}
};
Is is possible to do this for an arbitrary mpl::vector?
My test program looks like so:
int
main (int ac, char **av)
{
A a;
B b;
// test<A,B> t; //original
test<mpl::vector<A,B> > t; //mpl::vector with 2 ele开发者_如何学Cments
Slice<A>* Sa = &t;
Slice<B>* Sb = &t;
Sa->foo(a);
Sb->foo(b);
}
You want to use mpl::inherit_linearly
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