BLT/include/blt/std/ranges.h

711 lines
25 KiB
C++

#pragma once
/*
* Created by Brett on 06/02/24.
* Licensed under GNU General Public License V3.0
* See LICENSE file for license detail
*/
#ifndef BLT_RANGES_H
#define BLT_RANGES_H
#include <blt/std/types.h>
#include <blt/meta/meta.h>
#include <type_traits>
#include <iterator>
#include <memory>
#include <utility>
#include <limits>
namespace blt
{
namespace itr
{
template<typename Begin, typename End>
class itr_container
{
public:
itr_container(Begin&& begin, End&& end): begin_(std::forward<Begin>(begin)), end_(std::forward<End>(end))
{}
Begin begin()
{
return begin_;
}
End end()
{
return end_;
}
private:
Begin begin_;
End end_;
};
template<typename TYPE_ITR>
class iterator
{
public:
using iterator_category = std::forward_iterator_tag;
using value_type = typename std::iterator_traits<TYPE_ITR>::value_type;
using difference_type = typename std::iterator_traits<TYPE_ITR>::difference_type;
using pointer = typename std::iterator_traits<TYPE_ITR>::pointer;
using reference = typename std::iterator_traits<TYPE_ITR>::reference;
using const_reference = const reference;
private:
blt::size_t index;
TYPE_ITR current;
public:
explicit iterator(TYPE_ITR current, blt::size_t index): index(index), current(std::move(current))
{}
auto iter()
{
return current;
}
iterator& operator++()
{
++index;
++current;
return *this;
}
bool operator==(iterator other) const
{
return current == other.current;
}
bool operator!=(iterator other) const
{
return current != other.current;
}
std::pair<blt::size_t, blt::meta::deref_return_t<TYPE_ITR>> operator*() const
{
return {index, *current};
};
std::pair<blt::size_t, blt::meta::deref_return_t<TYPE_ITR>> operator*()
{
return {index, *current};
};
};
// TODO: cleanup! all of this! add support for reversing
template<typename C1_TYPE, typename C2_TYPE>
class pair_iterator
{
public:
using c1_ref = blt::meta::deref_return_t<C1_TYPE>;
using c2_ref = blt::meta::deref_return_t<C2_TYPE>;
using iterator_category = std::forward_iterator_tag;
using value_type = std::pair<c1_ref, c2_ref>;
using difference_type = blt::ptrdiff_t;
using pointer = void*;
using reference = value_type&;
using const_reference = const value_type&;
explicit pair_iterator(C1_TYPE c1, C2_TYPE c2): current_c1_iter(c1), current_c2_iter(c2)
{}
pair_iterator& operator++()
{
++current_c1_iter;
++current_c2_iter;
return *this;
}
bool operator==(pair_iterator other) const
{
return current_c1_iter == other.current_c1_iter && current_c2_iter == other.current_c2_iter;
}
bool operator!=(pair_iterator other) const
{
return current_c1_iter != other.current_c1_iter || current_c2_iter != other.current_c2_iter;
}
value_type operator*() const
{
return {*current_c1_iter, *current_c2_iter};
};
value_type operator*()
{
return {*current_c1_iter, *current_c2_iter};
};
private:
C1_TYPE current_c1_iter;
C2_TYPE current_c2_iter;
};
template<typename TYPE_ITR>
class reverse_iterator
{
public:
using iterator_category = std::forward_iterator_tag;
using value_type = typename std::iterator_traits<TYPE_ITR>::value_type;
using difference_type = typename std::iterator_traits<TYPE_ITR>::difference_type;
using pointer = typename std::iterator_traits<TYPE_ITR>::pointer;
using reference = typename std::iterator_traits<TYPE_ITR>::reference;
using const_reference = const reference;
private:
blt::size_t index;
TYPE_ITR current;
public:
explicit reverse_iterator(TYPE_ITR current, blt::size_t index): index(index), current(std::move(current))
{}
auto iter()
{
return current;
}
reverse_iterator& operator++()
{
--index;
--current;
return *this;
}
bool operator==(reverse_iterator other) const
{
return current == other.current;
}
bool operator!=(reverse_iterator other) const
{
return current != other.current;
}
std::pair<blt::size_t, const_reference> operator*() const
{
return {index, *current};
};
std::pair<blt::size_t, reference> operator*()
{
return {index, *current};
};
};
}
template<typename Begin, typename End>
static inline auto iterate(Begin&& begin, End&& end)
{
return itr::itr_container<Begin, End>{std::forward<Begin>(begin), std::forward<End>(end)};
}
template<typename Begin, typename End>
static inline auto reverse_iterate(Begin&& begin, End&& end)
{
return itr::itr_container{std::reverse_iterator(std::forward<Begin>(end)), std::reverse_iterator(std::forward<End>(begin))};
}
template<typename TYPE_ITR, template<typename> typename iterator = itr::iterator>
class enumerator
{
public:
explicit enumerator(TYPE_ITR begin, TYPE_ITR end): begin_(std::move(begin), 0), end_(std::move(end), 0)
{}
explicit enumerator(TYPE_ITR begin, TYPE_ITR end, blt::size_t i_begin, blt::size_t i_end):
begin_(std::move(begin), i_begin), end_(std::move(end), i_end)
{}
itr::iterator<TYPE_ITR> begin()
{
return begin_;
}
itr::iterator<TYPE_ITR> end()
{
return end_;
}
private:
iterator<TYPE_ITR> begin_;
iterator<TYPE_ITR> end_;
};
template<typename T>
static inline auto enumerate(const T& container)
{
return enumerator{container.begin(), container.end()};
}
template<typename T, blt::size_t size>
static inline auto enumerate(const T(& container)[size])
{
return enumerator{&container[0], &container[size]};
}
template<typename T, blt::size_t size>
static inline auto enumerate(T(& container)[size])
{
return enumerator{&container[0], &container[size]};
}
template<typename T>
static inline auto enumerate(T& container)
{
return enumerator{container.begin(), container.end()};
}
template<typename T>
static inline auto enumerate(T&& container)
{
return enumerator{container.begin(), container.end()};
}
template<typename C1_ITER, typename C2_ITER, template<typename, typename> typename iterator = itr::pair_iterator>
class pair_enumerator
{
public:
explicit pair_enumerator(C1_ITER c1_begin, C1_ITER c1_end, C2_ITER c2_begin, C2_ITER c2_end):
begin_(std::move(c1_begin), std::move(c2_begin)), end_(std::move(c1_end), std::move(c2_end))
{
auto size_c1 = c1_end - c1_begin;
auto size_c2 = c2_end - c2_begin;
if (size_c1 != size_c2)
throw std::runtime_error("Iterator sizes don't match!");
}
iterator<C1_ITER, C2_ITER> begin()
{
return begin_;
}
iterator<C1_ITER, C2_ITER> end()
{
return end_;
}
private:
iterator<C1_ITER, C2_ITER> begin_;
iterator<C1_ITER, C2_ITER> end_;
};
template<typename T, typename G>
static inline auto in_pairs(const T& container1, const G& container2)
{
return pair_enumerator{container1.begin(), container1.end(), container2.begin(), container2.end()};
}
template<typename T, typename G>
static inline auto in_pairs(T& container1, G& container2)
{
return pair_enumerator{container1.begin(), container1.end(), container2.begin(), container2.end()};
}
template<typename T, typename G, blt::size_t size>
static inline auto in_pairs(const T(& container1)[size], const G(& container2)[size])
{
return pair_enumerator{&container1[0], &container1[size], &container2[0], &container2[size]};
}
template<typename T, typename G, blt::size_t size>
static inline auto in_pairs(T(& container1)[size], G(& container2)[size])
{
return pair_enumerator{&container1[0], &container1[size], &container2[0], &container2[size]};
}
template<typename T, typename G>
static inline auto in_pairs(T&& container1, G&& container2)
{
return pair_enumerator{container1.begin(), container1.end(), container2.begin(), container2.end()};
}
template<typename T>
struct range
{
public:
struct range_itr
{
public:
using iterator_category = std::bidirectional_iterator_tag;
using difference_type = T;
using value_type = T;
using pointer = T*;
using reference = T&;
private:
T current;
bool forward;
public:
explicit range_itr(T current, bool forward): current(current), forward(forward)
{}
value_type operator*() const
{ return current; }
value_type operator->()
{ return current; }
range_itr& operator++()
{
if (forward)
current++;
else
current--;
return *this;
}
range_itr& operator--()
{
if (forward)
current--;
else
current++;
return *this;
}
friend bool operator==(const range_itr& a, const range_itr& b)
{
return a.current == b.current;
}
friend bool operator!=(const range_itr& a, const range_itr& b)
{
return a.current != b.current;
}
};
private:
T _begin;
T _end;
T offset = 0;
public:
range(T begin, T end): _begin(begin), _end(end), offset(end < begin ? 1 : 0)
{}
range_itr begin()
{
return range_itr(_begin - offset, offset == 0);
}
range_itr end()
{
// not sure if i like this
return range_itr(_end - offset, offset == 0);
}
};
template<typename I>
class itr_offset
{
private:
I begin_;
I end_;
public:
template<typename T>
itr_offset(I begin, I end, T offset): begin_(begin), end_(end)
{
for (T t = 0; t < offset; t++)
++begin_;
}
template<typename C, typename T>
itr_offset(C& container, T offset): begin_(container.begin()), end_(container.end())
{
for (T t = 0; t < offset; t++)
++begin_;
}
auto begin()
{
return begin_;
}
auto end()
{
return end_;
}
};
template<typename C, typename T>
itr_offset(C, T) -> itr_offset<typename C::iterator>;
inline constexpr std::size_t dynamic_extent = std::numeric_limits<std::size_t>::max();
template<typename T, std::size_t extent = dynamic_extent>
class span;
// https://codereview.stackexchange.com/questions/217814/c17-span-implementation
namespace span_detail
{
// detect specializations of span
template<class T>
struct is_span : std::false_type
{
};
template<class T, std::size_t N>
struct is_span<span<T, N>> : std::true_type
{
};
template<class T>
inline constexpr bool is_span_v = is_span<T>::value;
// detect specializations of std::array
template<class T>
struct is_array : std::false_type
{
};
template<class T, std::size_t N>
struct is_array<std::array<T, N>> : std::true_type
{
};
template<class T>
inline constexpr bool is_array_v = is_array<T>::value;
// detect container
template<class C, class = void>
struct is_cont : std::false_type
{
};
template<class C>
struct is_cont<C,
std::void_t<
std::enable_if_t<!is_span_v<C>>,
std::enable_if_t<!is_array_v<C>>,
std::enable_if_t<!std::is_array_v<C>>,
decltype(data(std::declval<C>())),
decltype(size(std::declval<C>()))
>> : std::true_type
{
};
template<class C>
inline constexpr bool is_cont_v = is_cont<C>::value;
}
template<typename T, std::size_t extent>
class span
{
public:
using element_type = T;
using value_type = std::remove_cv_t<T>;
using size_type = blt::size_t;
using difference_type = std::ptrdiff_t;
using pointer = T*;
using const_pointer = const T*;
using reference = T&;
using const_reference = const T&;
using iterator = T*;
using const_iterator = const T*;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
private:
size_type size_;
pointer data_;
public:
constexpr span() noexcept: size_(0), data_(nullptr)
{}
constexpr span(T* data, size_type count): size_(count), data_(data)
{}
template<class It, std::size_t SIZE, typename std::enable_if_t<extent != dynamic_extent && SIZE == extent, bool> = true>
constexpr explicit span(It first, size_type count): size_(count), data_(&*first)
{}
template<class It, std::size_t SIZE, typename std::enable_if_t<extent == dynamic_extent && SIZE == extent, bool> = true>
constexpr span(It first, size_type count): size_(count), data_(&*first)
{}
template<class It, class End, std::size_t SIZE, typename std::enable_if_t<extent != dynamic_extent && SIZE == extent, bool> = true>
constexpr explicit span(It first, End last): size_(&*last - &*first), data_(&*first)
{}
template<class It, class End, std::size_t SIZE, typename std::enable_if_t<extent == dynamic_extent && SIZE == extent, bool> = true>
constexpr span(It first, End last): size_(&*last - &*first), data_(&*first)
{}
template<std::size_t N, typename std::enable_if_t<(N == dynamic_extent || N == extent) &&
(std::is_convertible_v<std::remove_pointer_t<decltype(
std::data(std::declval<T(&)[N]>()))>(*)[], T(*)[]>), bool> = true>
constexpr span(element_type (& arr)[N]) noexcept: size_{N}, data_{arr} // NOLINT
{}
template<class U, std::size_t N, typename std::enable_if_t<(N == dynamic_extent || N == extent) &&
(std::is_convertible_v<std::remove_pointer_t<decltype(
std::data(std::declval<T(&)[N]>()))>(*)[], T(*)[]>), bool> = true>
constexpr span(std::array<U, N>& arr) noexcept: size_(N), data_{arr.data()} // NOLINT
{}
template<class U, std::size_t N, typename std::enable_if_t<(N == dynamic_extent || N == extent) &&
(std::is_convertible_v<std::remove_pointer_t<decltype(
std::data(std::declval<T(&)[N]>()))>(*)[], T(*)[]>), bool> = true>
constexpr span(const std::array<U, N>& arr) noexcept: size_(N), data_{arr.data()} // NOLINT
{}
template<class R, class RCV = std::remove_cv_t<std::remove_reference_t<R>>, typename std::enable_if_t<
extent != dynamic_extent && span_detail::is_cont_v<RCV> &&
std::is_convertible_v<std::remove_pointer_t<decltype(std::data(std::declval<R>()))>(*)[], T(*)[]>, bool> = true>
explicit constexpr span(R&& range): size_(std::size(range)), data_(std::data(range))
{}
template<class R, class RCV = std::remove_cv_t<std::remove_reference_t<R>>, typename std::enable_if_t<
extent == dynamic_extent && span_detail::is_cont_v<RCV> &&
std::is_convertible_v<std::remove_pointer_t<decltype(std::data(std::declval<R>()))>(*)[], T(*)[]>, bool> = true>
constexpr span(R&& range): size_(std::size(range)), data_(std::data(range)) // NOLINT
{}
template<size_type SIZE, typename std::enable_if_t<
extent != dynamic_extent && SIZE == extent && std::is_const_v<element_type>, bool> = true>
explicit constexpr span(std::initializer_list<value_type> il) noexcept: size_(il.size()), data_(&il.begin()) // NOLINT
{}
template<size_type SIZE, typename std::enable_if_t<
extent == dynamic_extent && SIZE == extent && std::is_const_v<element_type>, bool> = true>
explicit span(std::initializer_list<value_type> il) noexcept: size_(il.size()), data_(&il.begin()) // NOLINT
{}
template<class U, std::size_t N, typename std::enable_if_t<
extent != dynamic_extent && N == dynamic_extent && std::is_convertible_v<U(*)[], T(*)[]>, bool> = true>
explicit constexpr span(const span<U, N>& source) noexcept: size_{source.size()}, data_{source.data()}
{}
template<class U, std::size_t N, typename std::enable_if_t<
!(extent != dynamic_extent && N == dynamic_extent) && std::is_convertible_v<U(*)[], T(*)[]>, bool> = true>
constexpr span(const span<U, N>& source) noexcept: size_{source.size()}, data_{source.data()} // NOLINT
{}
constexpr span& operator=(const span& copy)
{
size_ = copy.size();
data_ = copy.data();
return *this;
}
constexpr span(const span& other) noexcept = default;
constexpr iterator begin() const noexcept
{
return data();
}
constexpr iterator end() const noexcept
{
return data() + size();
}
constexpr const_iterator cbegin() const noexcept
{
return data();
}
constexpr const_iterator cend() const noexcept
{
return data() + size();
}
constexpr reverse_iterator rbegin() const noexcept
{
return reverse_iterator{end()};
}
constexpr reverse_iterator rend() const noexcept
{
return reverse_iterator{begin()};
}
constexpr const_reverse_iterator crbegin() const noexcept
{
return reverse_iterator{cend()};
}
constexpr const_reverse_iterator crend() const noexcept
{
return reverse_iterator{cbegin()};
}
friend constexpr iterator begin(span s) noexcept
{
return s.begin();
}
friend constexpr iterator end(span s) noexcept
{
return s.end();
}
[[nodiscard]] constexpr size_type size() const noexcept
{
return size_;
}
[[nodiscard]] constexpr size_type size_bytes() const noexcept
{
return size() * sizeof(T);
}
[[nodiscard]] constexpr bool empty() const noexcept
{
return size() == 0;
}
constexpr reference operator[](size_type idx) const
{
return *(data() + idx);
}
constexpr reference front() const
{
return *data();
}
constexpr reference back() const
{
return *(data() + (size() - 1));
}
constexpr pointer data() const noexcept
{
return data_;
}
constexpr span<T, dynamic_extent> first(size_type cnt) const
{
return {data(), cnt};
}
constexpr span<T, dynamic_extent> last(size_type cnt) const
{
return {data() + (size() - cnt), cnt};
}
constexpr span<T, dynamic_extent> subspan(size_type off, size_type cnt = dynamic_extent) const
{
return {data() + off, cnt == dynamic_extent ? size() - off : cnt};
}
};
template<class T, std::size_t N>
span(T (&)[N]) -> span<T, N>;
template<class T, std::size_t N>
span(std::array<T, N>&) -> span<T, N>;
template<class T, std::size_t N>
span(const std::array<T, N>&) -> span<const T, N>;
template<class Cont>
span(Cont&) -> span<typename Cont::value_type>;
template<class Cont>
span(const Cont&) -> span<const typename Cont::value_type>;
}
#endif //BLT_RANGES_H