#ifndef ITERTOOLS_ITER_TUPLES_HPP_

#define ITERTOOLS_ITER_TUPLES_HPP_

#include "iterator_wrapper.hpp"

#include "iterbase.hpp"

#include <functional>

namespace iter {

namespace impl {

namespace detail {

template <typename... Ts>

std::tuple<iterator_deref<Ts>...> iterator_tuple_deref_helper(

const std::tuple<Ts...>&);

template <typename... Ts>

std::tuple<IteratorWrapper<Ts>...> iterator_tuple_type_helper(

const std::tuple<Ts...>&);

template <typename... Ts>

std::tuple<iterator_deref<const std::remove_reference_t<Ts>>...>

const_iterator_tuple_deref_helper(const std::tuple<Ts...>&);

template <typename... Ts>

std::tuple<IteratorWrapper<const std::remove_reference_t<Ts>>...>

const_iterator_tuple_type_helper(const std::tuple<Ts...>&);

}

// Given a tuple template argument, evaluates to a tuple of iterators

// for the template argument's contained types.

template <typename TupleType>

using iterator_tuple_type =

decltype(detail::iterator_tuple_type_helper(std::declval<TupleType>()));

template <typename TupleType>

using const_iterator_tuple_type = decltype(

detail::const_iterator_tuple_type_helper(std::declval<TupleType>()));

// Given a tuple template argument, evaluates to a tuple of

// what the iterators for the template argument's contained types

// dereference to

template <typename TupleType>

using iterator_deref_tuple = decltype(

detail::iterator_tuple_deref_helper(std::declval<TupleType>()));

template <typename TupleType>

using const_iterator_deref_tuple = decltype(

detail::const_iterator_tuple_deref_helper(std::declval<TupleType>()));

// function absorbing all arguments passed to it. used when

// applying a function to a parameter pack but not passing the evaluated

// results anywhere

template <typename... Ts>

void absorb(Ts&&...) {}

}

}

#endif