150 lines
4.5 KiB
C++
150 lines
4.5 KiB
C++
/*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
|
|
*/
|
|
|
|
#ifndef __UTIL_ADAPTER_HPP
|
|
#define __UTIL_ADAPTER_HPP
|
|
|
|
#include <array>
|
|
#include <cstddef>
|
|
#include <iterator>
|
|
|
|
namespace util::adapter {
|
|
namespace container {
|
|
// reverse a container for range-based-for
|
|
template <typename T>
|
|
struct reverse {
|
|
reverse (T &_target):
|
|
m_target (_target)
|
|
{ ; }
|
|
|
|
auto begin (void) { return m_target.begin (); }
|
|
auto end (void) { return m_target.end (); }
|
|
|
|
auto begin (void) const { return m_target.begin (); }
|
|
auto end (void) const { return m_target.end (); }
|
|
|
|
auto cbegin (void) { return m_target.cbegin (); }
|
|
auto cend (void) { return m_target.cend (); }
|
|
|
|
private:
|
|
T &m_target;
|
|
};
|
|
|
|
|
|
// adapt a container's range methods to return indices rather than iterators
|
|
template <typename T>
|
|
struct indices {
|
|
using typename T::size_type;
|
|
|
|
indices (T &_target):
|
|
m_target (_target)
|
|
{ ; }
|
|
|
|
size_type begin (void) { return 0; }
|
|
size_type end (void) { return m_target.size (); }
|
|
|
|
private:
|
|
T m_target;
|
|
};
|
|
}
|
|
|
|
namespace iterator {
|
|
// adapt an iterator to return the n-th tuple element of the
|
|
// underlying iterator::value_type
|
|
template <size_t I, typename It>
|
|
struct scalar : public std::iterator<
|
|
typename std::iterator_traits<It>::iterator_category,
|
|
typename std::tuple_element<
|
|
I,
|
|
typename std::iterator_traits<
|
|
It
|
|
>::value_type
|
|
>::type,
|
|
typename std::iterator_traits<It>::difference_type
|
|
> {
|
|
public:
|
|
using reference = typename std::iterator_traits<scalar<I,It>>::reference;
|
|
using value_type = typename std::iterator_traits<scalar<I,It>>::value_type;
|
|
|
|
scalar (It _inner):
|
|
m_inner (_inner)
|
|
{ ; }
|
|
|
|
const reference operator* (void) const
|
|
{ return std::get<I> (*m_inner); }
|
|
|
|
reference operator* (void)
|
|
{ return std::get<I> (*m_inner); }
|
|
|
|
bool operator== (scalar<I,It> rhs) { return m_inner == rhs.m_inner; }
|
|
bool operator!= (scalar<I,It> rhs) { return m_inner != rhs.m_inner; }
|
|
|
|
scalar<I,It>& operator++ (void)
|
|
{ ++m_inner; return *this; }
|
|
|
|
private:
|
|
It m_inner;
|
|
};
|
|
|
|
|
|
//template <
|
|
// typename It,
|
|
// size_t S,
|
|
// typename T
|
|
//>
|
|
//struct explode : public std::enable_if<
|
|
// std::is_same<
|
|
// typename std::iterator_traits<It>::value_type,
|
|
// std::array<T,S>
|
|
// >::value,
|
|
// typename std::iterator<
|
|
// typename std::iterator_traits<It>::iterator_category,
|
|
// typename std::tuple_element<
|
|
// typename std::iterator_traits<It>::value_type
|
|
// >::type,
|
|
// typename std::iterator_traits<It>::difference_type
|
|
// >::type
|
|
//> {
|
|
//public:
|
|
// explode (It _inner):
|
|
// m_inner (_inner),
|
|
// m_sequence (0)
|
|
// { ; }
|
|
|
|
// const reference operator* (void) const
|
|
// { return (*m_inner)[m_seqence]; }
|
|
|
|
// reference operator* (void)
|
|
// { return (*m_inner)[m_seqence]; }
|
|
|
|
// bool operator== (explode rhs) { return m_inner == rhs.m_inner && m_sequence == rhs.m_sequence; }
|
|
// bool operator!= (explode rhs) { return !(*this == rhs); }
|
|
|
|
// explode<It>& operator++ (void)
|
|
// {
|
|
// if (++m_sequence >= S)
|
|
// ++m_inner;
|
|
// }
|
|
|
|
//private:
|
|
// It m_inner;
|
|
// size_t m_sequence;
|
|
//};
|
|
}
|
|
}
|
|
|
|
#endif
|