Traits.h

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/*
 * Traits.h
 *
 *  Created on: 18 Dec 2017
 *      Author: Nicola Mori
 */

#ifndef TRAITS_H_
#define TRAITS_H_

#include <list>
#include <memory>
#include <type_traits>
#include <vector>

namespace EA {
// Traits for contained objects
template <template <typename> class test, typename T> struct smart_test : test<T> {};
template <template <typename> class test, typename T, typename A>
struct smart_test<test, std::vector<T, A>> : smart_test<test, typename std::decay<T>::type> {};
template <template <typename> class test, typename T, typename A>
struct smart_test<test, std::list<T, A>> : smart_test<test, typename std::decay<T>::type> {};

template <typename T>
using smart_is_copy_constructible = smart_test<std::is_copy_constructible, typename std::decay<T>::type>;

// Logical operators (see http://open-std.org/JTC1/SC22/WG21/docs/papers/2015/p0013r1.html)
template <class...> struct or_; // not defined
template <> struct or_<> : std::false_type {};
template <class B1, class B2> struct or_<B1, B2> : std::conditional_t<B1::value, B1, B2> {};

template <class...> struct and_; // not defined
template <> struct and_<> : std::true_type {};
template <class B1, class B2> struct and_<B1, B2> : std::conditional_t<B1::value, B2, B1> {};

template <class T> struct not_ : std::conditional_t<T::value, std::false_type, std::true_type> {};

// Pointer traits for detecting a pointer (possibly smart) to object
namespace _Private {
template <class T> struct is_pointer_helper : std::false_type {};

template <class T> struct is_pointer_helper<T *> : std::true_type {};

template <class T> struct is_pointer_helper<std::shared_ptr<T>> : std::true_type {};

template <class T> struct is_pointer_helper<std::unique_ptr<T>> : std::true_type {};

} // namespace _Private

template <class T> struct is_pointer : _Private::is_pointer_helper<typename std::remove_cv<T>::type> {};

} // namespace EA
#endif /* TRAITS_H_ */