Circulator/circulator_prog3.cpp

#include <cassert>
#include <list>
#include <CGAL/circulator.h>

template <class C> inline  int foo( C c, std::forward_iterator_tag) {
    CGAL::Assert_circulator( c);
    CGAL::Assert_forward_category( c);
    return 1;
}
template <class C> inline  int foo( C c, std::random_access_iterator_tag) {
    CGAL::Assert_circulator( c);
    CGAL::Assert_random_access_category( c);
    return 2;
}
template <class I> inline  int foo( I i, CGAL::Iterator_tag) {
    CGAL::Assert_iterator( i);
    return 3;
}

template <class C> inline  int foo( C c, CGAL::Circulator_tag) {
    CGAL::Assert_circulator( c);
    typedef std::iterator_traits<C> Traits;
    typedef typename Traits::iterator_category iterator_category;
    return foo( c, iterator_category());
}
template <class IC> inline  int foo( IC ic) {
    typedef CGAL::Circulator_traits<IC> Traits;
    typedef typename Traits::category category;
    return foo( ic, category());
}

int main() {
    typedef CGAL::Forward_circulator_base<int>       F;
    typedef CGAL::Random_access_circulator_base<int> R;
    F f = F();
    R r = R();
    std::list<int> l;
    assert( foo( f)         == 1);
    assert( foo( r)         == 2);
    assert( foo( l.begin()) == 3);
    return 0;
}