Standard library header <ranges>
This header is part of the ranges library.
Namespace aliases
namespace std {
namespace views = ranges::views;
} |
The namespace alias std::views is provided as a shorthand for std::ranges::views.
Concepts |
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Range concepts |
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Defined in namespace std::ranges |
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(C++20)
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specifies that a type is a range, that is, it provides a begin iterator and an end sentinel (concept) |
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(C++20)
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specifies that a type is a range and iterators obtained from an expression of it can be safely returned without danger of dangling (concept) |
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(C++20)
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specifies that a range knows its size in constant time (concept) |
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(C++20)
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specifies that a range is a view, that is, it has constant time copy/move/assignment (concept) |
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(C++20)
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specifies a range whose iterator type satisfies input_iterator (concept) |
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(C++20)
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specifies a range whose iterator type satisfies output_iterator (concept) |
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(C++20)
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specifies a range whose iterator type satisfies forward_iterator (concept) |
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(C++20)
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specifies a range whose iterator type satisfies bidirectional_iterator (concept) |
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(C++20)
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specifies a range whose iterator type satisfies random_access_iterator (concept) |
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(C++20)
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specifies a range whose iterator type satisfies contiguous_iterator (concept) |
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(C++20)
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specifies that a range has identical iterator and sentinel types (concept) |
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(C++20)
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specifies the requirements for a range to be safely convertible to a view (concept) |
Functions |
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Range conversions |
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Defined in namespace std::ranges |
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(C++23)
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constructs an object (usually a container) from a range (function template) |
Classes |
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Range primitives |
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Defined in namespace std::ranges |
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(C++20)
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obtains associated types of a range (alias template) |
Views |
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Defined in namespace std::ranges |
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(C++20)
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helper class template for defining a view, using the curiously recurring template pattern (class template) |
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(C++20)
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combines an iterator-sentinel pair into a view (class template) |
Dangling iterator handling |
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Defined in namespace std::ranges |
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(C++20)
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a placeholder type indicating that an iterator or a subrange should not be returned since it would be dangling (class) |
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(C++20)
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obtains iterator type or subrange type of a borrowed_range (alias template) |
Range adaptor objects utility |
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Defined in namespace std::ranges |
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(C++23)
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helper base class template for defining a range adaptor closure object (class template) |
Factories |
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Defined in namespace std::ranges |
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(C++20)
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an empty view with no elements (class template) (variable template) |
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(C++20)
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a view that contains a single element of a specified value (class template) (customization point object) |
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(C++20)
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a view consisting of a sequence generated by repeatedly incrementing an initial value (class template) (customization point object) |
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(C++20)
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a view consisting of the elements obtained by successive application of operator>> on the associated input stream (class template) (customization point object) |
Adaptors |
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Defined in namespace std::ranges |
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(C++20)
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a view that includes all elements of a range (alias template) (range adaptor object) |
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(C++20)
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a view of the elements of some other range (class template) |
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(C++20)
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a view with unique ownership of some range (class template) |
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(C++20)
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a view that consists of the elements of a range that satisfies a predicate (class template) (range adaptor object) |
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(C++20)
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a view of a sequence that applies a transformation function to each element (class template) (range adaptor object) |
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(C++20)
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a view consisting of the first N elements of another view (class template) (range adaptor object) |
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(C++20)
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a view consisting of the initial elements of another view, until the first element on which a predicate returns false (class template) (range adaptor object) |
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(C++20)
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a view consisting of elements of another view, skipping the first N elements (class template) (range adaptor object) |
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(C++20)
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a view consisting of the elements of another view, skipping the initial subsequence of elements until the first element where the predicate returns false (class template) (range adaptor object) |
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(C++20)
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a view consisting of the sequence obtained from flattening a view of ranges (class template) (range adaptor object) |
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(C++20)
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a view over the subranges obtained from splitting another view using a delimiter (class template) (range adaptor object) |
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(C++20)
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a view over the subranges obtained from splitting another view using a delimiter (class template) (range adaptor object) |
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(C++20)
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creates a subrange from an iterator and a count (customization point object) |
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(C++20)
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converts a view into a common_range (class template) (range adaptor object) |
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(C++20)
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a view that iterates over the elements of another bidirectional view in reverse order (class template) (range adaptor object) |
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(C++20)
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takes a view consisting of tuple-like values and a number N and produces a view of N'th element of each tuple (class template) (range adaptor object) |
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(C++20)
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takes a view consisting of pair-like values and produces a view of the first elements of each pair (class template) (range adaptor object) |
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(C++20)
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takes a view consisting of pair-like values and produces a view of the second elements of each pair (class template) (range adaptor object) |
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(C++23)
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a view consisting of tuples of references to corresponding elements of the adapted views (class template) (customization point object) |
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(C++23)
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a view consisting of tuples of results of application of a transformation function to corresponding elements of the adapted views (class template) (customization point object) |
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(C++23)
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a view consisting of tuples of references to adjacent elements of the adapted view (class template) (range adaptor object) |
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(C++23)
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a view consisting of tuples of results of application of a transformation function to adjacent elements of the adapted view (class template) (range adaptor object) |
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(C++23)
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a view consisting of the sequence obtained from flattening a view of ranges, with the delimiter in between elements (class template) (range adaptor object) |
Customization point objects |
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Range access |
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Defined in namespace std::ranges |
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(C++20)
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returns an iterator to the beginning of a range (customization point object) |
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(C++20)
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returns a sentinel indicating the end of a range (customization point object) |
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(C++20)
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returns an iterator to the beginning of a read-only range (customization point object) |
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(C++20)
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returns a sentinel indicating the end of a read-only range (customization point object) |
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(C++20)
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returns a reverse iterator to a range (customization point object) |
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(C++20)
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returns a reverse end iterator to a range (customization point object) |
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(C++20)
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returns a reverse iterator to a read-only range (customization point object) |
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(C++20)
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returns a reverse end iterator to a read-only range (customization point object) |
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(C++20)
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returns an integer equal to the size of a range (customization point object) |
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(C++20)
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returns a signed integer equal to the size of a range (customization point object) |
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(C++20)
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checks whether a range is empty (customization point object) |
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(C++20)
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obtains a pointer to the beginning of a contiguous range (customization point object) |
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(C++20)
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obtains a pointer to the beginning of a read-only contiguous range (customization point object) |
Enumerations |
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Defined in namespace std::ranges |
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(C++20)
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specifies whether a std::ranges::subrange models std::ranges::sized_range (enum) |
Helpers |
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(C++23)
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from-range construction tag (class) |
Synopsis
#include <compare>
#include <initializer_list>
#include <iterator>
namespace std::ranges {
inline namespace /* unspecified */ {
// range access
inline constexpr /* unspecified */ begin = /* unspecified */;
inline constexpr /* unspecified */ end = /* unspecified */;
inline constexpr /* unspecified */ cbegin = /* unspecified */;
inline constexpr /* unspecified */ cend = /* unspecified */;
inline constexpr /* unspecified */ rbegin = /* unspecified */;
inline constexpr /* unspecified */ rend = /* unspecified */;
inline constexpr /* unspecified */ crbegin = /* unspecified */;
inline constexpr /* unspecified */ crend = /* unspecified */;
inline constexpr /* unspecified */ size = /* unspecified */;
inline constexpr /* unspecified */ ssize = /* unspecified */;
inline constexpr /* unspecified */ empty = /* unspecified */;
inline constexpr /* unspecified */ data = /* unspecified */;
inline constexpr /* unspecified */ cdata = /* unspecified */;
}
// ranges
template<class T>
concept range = /* see description */;
template<class T>
inline constexpr bool enable_borrowed_range = false;
template<class T>
concept borrowed_range = /* see description */;
template<class T>
using iterator_t = decltype(ranges::begin(declval<T&>()));
template<range R>
using sentinel_t = decltype(ranges::end(declval<R&>()));
template<range R>
using range_difference_t = iter_difference_t<iterator_t<R>>;
template<sized_range R>
using range_size_t = decltype(ranges::size(declval<R&>()));
template<range R>
using range_value_t = iter_value_t<iterator_t<R>>;
template<range R>
using range_reference_t = iter_reference_t<iterator_t<R>>;
template<range R>
using range_rvalue_reference_t = iter_rvalue_reference_t<iterator_t<R>>;
// sized ranges
template<class>
inline constexpr bool disable_sized_range = false;
template<class T>
concept sized_range = /* see description */;
// views
template<class T>
inline constexpr bool enable_view = /* see description */;
struct view_base {};
template<class T>
concept view = /* see description */;
// other range refinements
template<class R, class T>
concept output_range = /* see description */;
template<class T>
concept input_range = /* see description */;
template<class T>
concept forward_range = /* see description */;
template<class T>
concept bidirectional_range = /* see description */;
template<class T>
concept random_access_range = /* see description */;
template<class T>
concept contiguous_range = /* see description */;
template<class T>
concept common_range = /* see description */;
template<class T>
concept viewable_range = /* see description */;
// class template view_interface
template<class D>
requires is_class_v<D> && same_as<D, remove_cv_t<D>>
class view_interface;
// sub-ranges
enum class subrange_kind : bool { unsized, sized };
template<input_or_output_iterator I, sentinel_for<I> S = I, subrange_kind K =
sized_sentinel_for<S, I> ? subrange_kind::sized : subrange_kind::unsized>
requires (K == subrange_kind::sized || !sized_sentinel_for<S, I>)
class subrange;
template<class I, class S, subrange_kind K>
inline constexpr bool enable_borrowed_range<subrange<I, S, K>> = true;
// dangling iterator handling
struct dangling;
template<range R>
using borrowed_iterator_t = /* see description */;
template<range R>
using borrowed_subrange_t = /* see description */;
// range conversions
template<class C, input_range R, class... Args> requires (!view<C>)
constexpr C to(R&& r, Args&&... args);
template<template<class...> class C, input_range R, class... Args>
constexpr auto to(R&& r, Args&&... args) -> /* see description */;
template<class C, class... Args> requires (!view<C>)
constexpr auto to(Args&&... args) -> /* see description */;
template<template<class...> class C, class... Args>
constexpr auto to(Args&&... args) -> /* see description */;
// empty view
template<class T>
requires is_object_v<T>
class empty_view;
template<class T>
inline constexpr bool enable_borrowed_range<empty_view<T>> = true;
namespace views {
template<class T>
inline constexpr empty_view<T> empty{};
}
// single view
template<copy_constructible T>
requires is_object_v<T>
class single_view;
namespace views { inline constexpr /* unspecified */ single = /* unspecified */; }
template<bool Const, class T>
using /*maybe-const*/ = conditional_t<Const, const T, T>; // exposition only
// iota view
template<weakly_incrementable W, semiregular Bound = unreachable_sentinel_t>
requires /*weakly-equality-comparable-with*/<W, Bound> && copyable<W>
class iota_view;
template<class W, class Bound>
inline constexpr bool enable_borrowed_range<iota_view<W, Bound>> = true;
namespace views { inline constexpr /* unspecified */ iota = /* unspecified */; }
// istream view
template<movable Val, class CharT, class Traits = char_traits<CharT>>
requires /* see description */
class basic_istream_view;
template<class Val>
using istream_view = basic_istream_view<Val, char>;
template<class Val>
using wistream_view = basic_istream_view<Val, wchar_t>;
namespace views { template<class T>
inline constexpr /* unspecified */ istream = /* unspecified */; }
// range adaptor objects
template<class D>
requires is_class_v<D> && same_as<D, remove_cv_t<D>>
class range_adaptor_closure { };
// all view
namespace views {
inline constexpr /* unspecified */ all = /* unspecified */;
template<viewable_range R>
using all_t = decltype(all(declval<R>()));
}
template<range R>
requires is_object_v<R>
class ref_view;
template<class T>
inline constexpr bool enable_borrowed_range<ref_view<T>> = true;
// owning view
template<range R>
requires /* see description */
class owning_view;
template<class T>
inline constexpr bool enable_borrowed_range<owning_view<T>> =
enable_borrowed_range<T>;
// filter view
template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class filter_view;
namespace views { inline constexpr /* unspecified */ filter = /* unspecified */; }
// transform view
template<input_range V, copy_constructible F>
requires view<V> && is_object_v<F> &&
regular_invocable<F&, range_reference_t<V>> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<V>>>
class transform_view;
namespace views { inline constexpr /* unspecified */ transform = /* unspecified */; }
// take view
template<view> class take_view;
template<class T>
inline constexpr bool enable_borrowed_range<take_view<T>> = enable_borrowed_range<T>;
namespace views { inline constexpr /* unspecified */ take = /* unspecified */; }
// take while view
template<view V, class Pred>
requires input_range<V> && is_object_v<Pred> &&
indirect_unary_predicate<const Pred, iterator_t<V>>
class take_while_view;
namespace views { inline constexpr /* unspecified */ take_while = /* unspecified */; }
// drop view
template<view V>
class drop_view;
template<class T>
inline constexpr bool enable_borrowed_range<drop_view<T>> = enable_borrowed_range<T>;
namespace views { inline constexpr /* unspecified */ drop = /* unspecified */; }
// drop while view
template<view V, class Pred>
requires input_range<V> && is_object_v<Pred> &&
indirect_unary_predicate<const Pred, iterator_t<V>>
class drop_while_view;
template<class T, class Pred>
inline constexpr bool enable_borrowed_range<drop_while_view<T, Pred>> =
enable_borrowed_range<T>;
namespace views { inline constexpr /* unspecified */ drop_while = /* unspecified */; }
// join view
template<input_range V>
requires view<V> && input_range<range_reference_t<V>>
class join_view;
namespace views { inline constexpr /* unspecified */ join = /* unspecified */; }
// join with view
template<class R, class P>
concept /*compatible-joinable-ranges*/ = /* see description */;
template<input_range V, forward_range Pattern>
requires view<V> && input_range<range_reference_t<V>>
&& view<Pattern>
&& /*compatible-joinable-ranges*/<range_reference_t<V>, Pattern>
class join_with_view;
namespace view { inline constexpr /* unspecified */ join_with = /* unspecified */; }
// lazy split view
template<class R>
concept /*tiny-range*/ = /* see description */; // exposition only
template<input_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
&& (forward_range<V> || /*tiny-range*/<Pattern>)
class lazy_split_view;
// split view
template<forward_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
class split_view;
namespace views {
inline constexpr /* unspecified */ lazy_split = /* unspecified */;
inline constexpr /* unspecified */ split = /* unspecified */;
}
// counted view
namespace views { inline constexpr /* unspecified */ counted = /* unspecified */; }
// common view
template<view V>
requires (!common_range<V> && copyable<iterator_t<V>>)
class common_view;
template<class T>
inline constexpr bool enable_borrowed_range<common_view<T>> =
enable_borrowed_range<T>;
namespace views { inline constexpr /* unspecified */ common = /* unspecified */; }
// reverse view
template<view V>
requires bidirectional_range<V>
class reverse_view;
template<class T>
inline constexpr bool enable_borrowed_range<reverse_view<T>> =
enable_borrowed_range<T>;
namespace views { inline constexpr /* unspecified */ reverse = /* unspecified */; }
// elements view
template<input_range V, size_t N>
requires /* see description */
class elements_view;
template<class T, size_t N>
inline constexpr bool enable_borrowed_range<elements_view<T, N>> =
enable_borrowed_range<T>;
template<class R>
using keys_view = elements_view<R, 0>;
template<class R>
using values_view = elements_view<R, 1>;
namespace views {
template<size_t N>
inline constexpr /* unspecified */ elements = /* unspecified */;
inline constexpr auto keys = elements<0>;
inline constexpr auto values = elements<1>;
}
// zip view
template<input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0)
class zip_view;
template<class... Views>
inline constexpr bool enable_borrowed_range<zip_view<Views...>> =
(enable_borrowed_range<Views> && ...);
namespace views { inline constexpr /* unspecified */ zip = /* unspecified */; }
// zip transform view
template<copy_constructible F, input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0) && is_object_v<F> &&
regular_invocable<F&, range_reference_t<Views>...> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<Views>...>>
class zip_transform_view;
namespace views {
inline constexpr /* unspecified */ zip_transform = /* unspecified */; }
// adjacent view
template<forward_range V, size_t N>
requires view<V> && (N > 0)
class adjacent_view;
template<class V, size_t N>
inline constexpr bool enable_borrowed_range<adjacent_view<V, N>> =
enable_borrowed_range<V>;
namespace views {
template<size_t N>
inline constexpr /* unspecified */ adjacent = /* unspecified */ ;
inline constexpr auto pairwise = adjacent<2>;
}
// adjacent transform view
template<forward_range V, copy_constructible F, size_t N>
requires /* see description */
class adjacent_transform_view;
namespace views {
template<size_t N>
inline constexpr /* unspecified */ adjacent_transform = /* unspecified */;
inline constexpr auto pairwise_transform = adjacent_transform<2>;
}
// chunk view
template<view V>
requires input_range<V>
class chunk_view;
template<view V>
requires forward_range<V>
class chunk_view<V>;
template<class V>
inline constexpr bool enable_borrowed_range<chunk_view<V>> =
forward_range<V> && enable_borrowed_range<V>;
namespace views { inline constexpr /* unspecified */ chunk = /* unspecified */; }
// slide view
template<view V>
requires forward_range<V>
class slide_view;
template<class V>
inline constexpr bool enable_borrowed_range<slide_view<V>> =
enable_borrowed_range<V>;
namespace views { inline constexpr /* unspecified */ slide = /* unspecified */; }
// chunk by view
template<forward_range V, indirect_binary_predicate<iterator_t<V>, iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class chunk_by_view;
namespace views { inline constexpr /* unspecified */ chunk_by = /* unspecified */; }
}
namespace std {
namespace views = ranges::views;
template<class T> struct tuple_size;
template<size_t I, class T> struct tuple_element;
template<class I, class S, ranges::subrange_kind K>
struct tuple_size<ranges::subrange<I, S, K>>
: integral_constant<size_t, 2> {};
template<class I, class S, ranges::subrange_kind K>
struct tuple_element<0, ranges::subrange<I, S, K>> {
using type = I;
};
template<class I, class S, ranges::subrange_kind K>
struct tuple_element<1, ranges::subrange<I, S, K>> {
using type = S;
};
template<class I, class S, ranges::subrange_kind K>
struct tuple_element<0, const ranges::subrange<I, S, K>> {
using type = I;
};
template<class I, class S, ranges::subrange_kind K>
struct tuple_element<1, const ranges::subrange<I, S, K>> {
using type = S;
};
struct from_range_t { explicit from_range_t() = default; };
inline constexpr from_range_t from_range{};
}
Concept range
namespace std::ranges {
template< class T >
concept range = requires(T& t) {
ranges::begin(t); // equality-preserving for forward iterators
ranges::end(t);
};
}
Concept borrowed_range
namespace std::ranges {
template<class T>
concept borrowed_range =
range<T> && (is_lvalue_reference_v<T> ||
enable_borrowed_range<remove_cvref_t<T>>);
}
Concept sized_range
namespace std::ranges {
template< class T >
concept sized_range = range<T> &&
requires(T& t) {
ranges::size(t);
};
}
Concept view
namespace std::ranges {
template<class T>
inline constexpr bool enable_view = derived_from<T, view_base>;
template<class T>
concept view = range<T>
&& movable<T>
&& enable_view<T>;
}
Concept output_range
namespace std::ranges {
template<class R, class T>
concept output_range =
range<R> && output_iterator<iterator_t<R>, T>;
}
Concept input_range
namespace std::ranges {
template<class T>
concept input_range =
range<T> && input_iterator<iterator_t<T>>;
}
Concept forward_range
namespace std::ranges {
template<class T>
concept forward_range =
input_range<T> && forward_iterator<iterator_t<T>>;
}
Concept bidirectional_range
namespace std::ranges {
template<class T>
concept bidirectional_range =
forward_range<T> && bidirectional_iterator<iterator_t<T>>;
}
Concept random_access_range
namespace std::ranges {
template<class T>
concept random_access_range =
bidirectional_range<T> && random_access_iterator<iterator_t<T>>;
}
Concept contiguous_range
namespace std::ranges {
template<class T>
concept contiguous_range =
random_access_range<T> && contiguous_iterator<iterator_t<T>> &&
requires(T& t) {
{ ranges::data(t) } -> same_as<add_pointer_t<range_reference_t<T>>>;
};
}
Concept common_range
namespace std::ranges {
template<class T>
concept common_range =
range<T> && same_as<iterator_t<T>, sentinel_t<T>>;
}
Concept viewable_range
namespace std::ranges {
template<class T>
concept viewable_range =
range<T> && (borrowed_range<T> || view<remove_cvref_t<T>>);
}
Helper concepts
namespace std::ranges { // unspecified, for name lookup only
template<class R>
concept /*simple-view*/ = // exposition only
view<R> && range<const R> &&
same_as<iterator_t<R>, iterator_t<const R>> &&
same_as<sentinel_t<R>, sentinel_t<const R>>;
template<class I>
concept /*has-arrow*/ = // exposition only
input_iterator<I> &&
(is_pointer_v<I> || requires(I i) { i.operator->(); });
template<class T, class U>
concept /*different-from*/ = // exposition only
!same_as<remove_cvref_t<T>, remove_cvref_t<U>>;
template<class I>
concept /*decrementable*/ = // exposition only
incrementable<I> && requires(I i) {
{ --i } -> same_as<I&>;
{ i-- } -> same_as<I>;
};
template<class I>
concept /*advanceable*/ = // exposition only
/*decrementable*/<I> && totally_ordered<I> &&
requires(I i, const I j, const iter_difference_t<I> n) {
{ i += n } -> same_as<I&>;
{ i -= n } -> same_as<I&>;
I { j + n };
I { n + j };
I { j - n };
{ j - j } -> convertible_to<iter_difference_t<I>>;
};
}
Note: These names are only for exposition, they are not part of the interface.
Class template std::ranges::view_interface
namespace std::ranges {
template<class D>
requires is_class_v<D> && same_as<D, remove_cv_t<D>>
class view_interface {
private:
constexpr D& derived() noexcept { // exposition only
return static_cast<D&>(*this);
}
constexpr const D& derived() const noexcept { // exposition only
return static_cast<const D&>(*this);
}
public:
constexpr bool empty() requires forward_range<D> {
return ranges::begin(derived()) == ranges::end(derived());
}
constexpr bool empty() const requires forward_range<const D> {
return ranges::begin(derived()) == ranges::end(derived());
}
constexpr explicit operator bool()
requires requires { ranges::empty(derived()); } {
return !ranges::empty(derived());
}
constexpr explicit operator bool() const
requires requires { ranges::empty(derived()); } {
return !ranges::empty(derived());
}
constexpr auto data() requires contiguous_iterator<iterator_t<D>> {
return to_address(ranges::begin(derived()));
}
constexpr auto data() const
requires range<const D> && contiguous_iterator<iterator_t<const D>> {
return to_address(ranges::begin(derived()));
}
constexpr auto size() requires forward_range<D> &&
sized_sentinel_for<sentinel_t<D>, iterator_t<D>> {
return ranges::end(derived()) - ranges::begin(derived());
}
constexpr auto size() const requires forward_range<const D> &&
sized_sentinel_for<sentinel_t<const D>, iterator_t<const D>> {
return ranges::end(derived()) - ranges::begin(derived());
}
constexpr decltype(auto) front() requires forward_range<D>;
constexpr decltype(auto) front() const requires forward_range<const D>;
constexpr decltype(auto) back() requires bidirectional_range<D> && common_range<D>;
constexpr decltype(auto) back() const
requires bidirectional_range<const D> && common_range<const D>;
template<random_access_range R = D>
constexpr decltype(auto) operator[](range_difference_t<R> n) {
return ranges::begin(derived())[n];
}
template<random_access_range R = const D>
constexpr decltype(auto) operator[](range_difference_t<R> n) const {
return ranges::begin(derived())[n];
}
};
}
Class template std::ranges::subrange
namespace std::ranges {
template<class From, class To>
concept /*uses-nonqualification-pointer-conversion*/ = // exposition only
is_pointer_v<From> && is_pointer_v<To> &&
!convertible_to<remove_pointer_t<From>(*)[], remove_pointer_t<To>(*)[]>;
template<class From, class To>
concept /*convertible-to-non-slicing*/ = // exposition only
convertible_to<From, To> &&
!/*uses-nonqualification-pointer-conversion*/<decay_t<From>, decay_t<To>>;
template<class T>
concept /*pair-like*/ = // exposition only
!is_reference_v<T> && requires(T t) {
typename tuple_size<T>::type; // ensures tuple_size<T>
// is complete
requires derived_from<tuple_size<T>, integral_constant<size_t, 2>>;
typename tuple_element_t<0, remove_const_t<T>>;
typename tuple_element_t<1, remove_const_t<T>>;
{ std::get<0>(t) } -> convertible_to<const tuple_element_t<0, T>&>;
{ std::get<1>(t) } -> convertible_to<const tuple_element_t<1, T>&>;
};
template<class T, class U, class V>
concept /*pair-like-convertible-from*/ = // exposition only
!range<T> && /*pair-like*/<T> &&
constructible_from<T, U, V> &&
/*convertible-to-non-slicing*/<U, tuple_element_t<0, T>> &&
convertible_to<V, tuple_element_t<1, T>>;
template<input_or_output_iterator I, sentinel_for<I> S = I, subrange_kind K =
sized_sentinel_for<S, I> ? subrange_kind::sized : subrange_kind::unsized>
requires (K == subrange_kind::sized || !sized_sentinel_for<S, I>)
class subrange : public view_interface<subrange<I, S, K>> {
private:
static constexpr bool StoreSize = // exposition only
K == subrange_kind::sized && !sized_sentinel_for<S, I>;
I begin_ = I(); // exposition only
S end_ = S(); // exposition only
/*make-unsigned-like-t*/<iter_difference_t<I>> size_ = 0; // exposition only;
// present only
// when StoreSize is true
public:
subrange() requires default_initializable<I> = default;
constexpr subrange(/*convertible-to-non-slicing*/<I> auto i, S s)
requires (!StoreSize);
constexpr subrange(/*convertible-to-non-slicing*/<I> auto i, S s,
/*make-unsigned-like-t*/<iter_difference_t<I>> n)
requires (K == subrange_kind::sized);
template</*different-from*/<subrange> R>
requires borrowed_range<R> &&
/*convertible-to-non-slicing*/<iterator_t<R>, I> &&
convertible_to<sentinel_t<R>, S>
constexpr subrange(R&& r) requires (!StoreSize || sized_range<R>);
template<borrowed_range R>
requires /*convertible-to-non-slicing*/<iterator_t<R>, I> &&
convertible_to<sentinel_t<R>, S>
constexpr subrange(R&& r, /*make-unsigned-like-t*/<iter_difference_t<I>> n)
requires (K == subrange_kind::sized)
: subrange{ranges::begin(r), ranges::end(r), n} {}
template</*different-from*/<subrange> PairLike>
requires /*pair-like-convertible-from*/<PairLike, const I&, const S&>
constexpr operator PairLike() const;
constexpr I begin() const requires copyable<I>;
[[nodiscard]] constexpr I begin() requires (!copyable<I>);
constexpr S end() const;
constexpr bool empty() const;
constexpr /*make-unsigned-like-t*/<iter_difference_t<I>> size() const
requires (K == subrange_kind::sized);
[[nodiscard]] constexpr subrange next(iter_difference_t<I> n = 1) const &
requires forward_iterator<I>;
[[nodiscard]] constexpr subrange next(iter_difference_t<I> n = 1) &&;
[[nodiscard]] constexpr subrange prev(iter_difference_t<I> n = 1) const
requires bidirectional_iterator<I>;
constexpr subrange& advance(iter_difference_t<I> n);
};
template<input_or_output_iterator I, sentinel_for<I> S>
subrange(I, S) -> subrange<I, S>;
template<input_or_output_iterator I, sentinel_for<I> S>
subrange(I, S, /*make-unsigned-like-t*/<iter_difference_t<I>>) ->
subrange<I, S, subrange_kind::sized>;
template<borrowed_range R>
subrange(R&&) ->
subrange<iterator_t<R>, sentinel_t<R>,
(sized_range<R> || sized_sentinel_for<sentinel_t<R>, iterator_t<R>>)
? subrange_kind::sized : subrange_kind::unsized>;
template<borrowed_range R>
subrange(R&&, /*make-unsigned-like-t*/<range_difference_t<R>>) ->
subrange<iterator_t<R>, sentinel_t<R>, subrange_kind::sized>;
template<size_t N, class I, class S, subrange_kind K>
requires ((N == 0 && copyable<I>) || N == 1)
constexpr auto get(const subrange<I, S, K>& r);
template<size_t N, class I, class S, subrange_kind K>
requires (N < 2)
constexpr auto get(subrange<I, S, K>&& r);
}
namespace std {
using ranges::get;
}
Class std::ranges::dangling
namespace std::ranges {
struct dangling {
constexpr dangling() noexcept = default;
constexpr dangling(auto&&...) noexcept {}
};
}
Class template std::ranges::empty_view
namespace std::ranges {
template<class T>
requires is_object_v<T>
class empty_view : public view_interface<empty_view<T>> {
public:
static constexpr T* begin() noexcept { return nullptr; }
static constexpr T* end() noexcept { return nullptr; }
static constexpr T* data() noexcept { return nullptr; }
static constexpr size_t size() noexcept { return 0; }
static constexpr bool empty() noexcept { return true; }
};
}
Class template std::ranges::single_view
namespace std::ranges {
template<copy_constructible T>
requires is_object_v<T>
class single_view : public view_interface<single_view<T>> {
private:
/*copyable-box*/<T> value_; // exposition only
public:
single_view() requires default_initializable<T> = default;
constexpr explicit single_view(const T& t);
constexpr explicit single_view(T&& t);
template<class... Args>
requires constructible_from<T, Args...>
constexpr explicit single_view(in_place_t, Args&&... args);
constexpr T* begin() noexcept;
constexpr const T* begin() const noexcept;
constexpr T* end() noexcept;
constexpr const T* end() const noexcept;
static constexpr size_t size() noexcept;
constexpr T* data() noexcept;
constexpr const T* data() const noexcept;
};
template<class T>
single_view(T) -> single_view<T>;
}
Class template std::ranges::iota_view
namespace std::ranges {
template<class I>
concept decrementable = /* see description */; // exposition only
template<class I>
concept advanceable = /* see description */; // exposition only
template<weakly_incrementable W, semiregular Bound = unreachable_sentinel_t>
requires /*weakly-equality-comparable-with*/<W, Bound> && copyable<W>
class iota_view : public view_interface<iota_view<W, Bound>> {
private:
// class iota_view::iterator
struct iterator; // exposition only
// class iota_view::sentinel
struct sentinel; // exposition only
W value_ = W(); // exposition only
Bound bound_ = Bound(); // exposition only
public:
iota_view() requires default_initializable<W> = default;
constexpr explicit iota_view(W value);
constexpr iota_view(type_identity_t<W> value, type_identity_t<Bound> bound);
constexpr iota_view(iterator first, /* see description */ last);
constexpr iterator begin() const;
constexpr auto end() const;
constexpr iterator end() const requires same_as<W, Bound>;
constexpr auto size() const requires /* see description */;
};
template<class W, class Bound>
requires (!/*is-integer-like*/<W> || !/*is-integer-like*/<Bound> ||
(/*is-signed-integer-like*/<W> == /*is-signed-integer-like*/<Bound>))
iota_view(W, Bound) -> iota_view<W, Bound>;
}
Class std::ranges::iota_view::iterator
namespace std::ranges {
template<weakly_incrementable W, semiregular Bound>
requires /*weakly-equality-comparable-with*/<W, Bound> && copyable<W>
struct iota_view<W, Bound>::iterator {
private:
W value_ = W(); // exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = input_iterator_tag; // present only if W models incrementable
using value_type = W;
using difference_type = /*IOTA-DIFF-T*/(W);
iterator() requires default_initializable<W> = default;
constexpr explicit iterator(W value);
constexpr W operator*() const noexcept(is_nothrow_copy_constructible_v<W>);
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires incrementable<W>;
constexpr iterator& operator--() requires /*decrementable*/<W>;
constexpr iterator operator--(int) requires /*decrementable*/<W>;
constexpr iterator& operator+=(difference_type n)
requires /*advanceable*/<W>;
constexpr iterator& operator-=(difference_type n)
requires /*advanceable*/<W>;
constexpr W operator[](difference_type n) const
requires /*advanceable*/<W>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires equality_comparable<W>;
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires totally_ordered<W>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires totally_ordered<W>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires totally_ordered<W>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires totally_ordered<W>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires totally_ordered<W> && three_way_comparable<W>;
friend constexpr iterator operator+(iterator i, difference_type n)
requires /*advanceable*/<W>;
friend constexpr iterator operator+(difference_type n, iterator i)
requires /*advanceable*/<W>;
friend constexpr iterator operator-(iterator i, difference_type n)
requires /*advanceable*/<W>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires /*advanceable*/<W>;
};
}
Class std::ranges::iota_view::sentinel
namespace std::ranges {
template<weakly_incrementable W, semiregular Bound>
requires /*weakly-equality-comparable-with*/<W, Bound> && copyable<W>
struct iota_view<W, Bound>::sentinel {
private:
Bound bound_ = Bound(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(Bound bound);
friend constexpr bool operator==(const iterator& x, const sentinel& y);
friend constexpr iter_difference_t<W> operator-(const iterator& x, const sentinel& y)
requires sized_sentinel_for<Bound, W>;
friend constexpr iter_difference_t<W> operator-(const sentinel& x, const iterator& y)
requires sized_sentinel_for<Bound, W>;
};
}
Class template std::ranges::basic_istream_view
namespace std::ranges {
template<class Val, class CharT, class Traits>
concept /*stream-extractable*/ = // exposition only
requires(basic_istream<CharT, Traits>& is, Val& t) {
is >> t;
};
template<movable Val, class CharT, class Traits = char_traits<CharT>>
requires default_initializable<Val> &&
/*stream-extractable*/<Val, CharT, Traits>
class basic_istream_view :
public view_interface<basic_istream_view<Val, CharT, Traits>> {
public:
constexpr explicit basic_istream_view(basic_istream<CharT, Traits>& stream);
constexpr auto begin() {
*stream_ >> value_;
return iterator{*this};
}
constexpr default_sentinel_t end() const noexcept;
private:
struct iterator; // exposition only
basic_istream<CharT, Traits>* stream_; // exposition only
Val value_ = Val(); // exposition only
};
}
Class template std::ranges::basic_istream_view::iterator
namespace std::ranges {
template<movable Val, class CharT, class Traits>
requires default_initializable<Val> &&
/*stream-extractable*/<Val, CharT, Traits>
class basic_istream_view<Val, CharT, Traits>::iterator {
public:
using iterator_concept = input_iterator_tag;
using difference_type = ptrdiff_t;
using value_type = Val;
constexpr explicit iterator(basic_istream_view& parent) noexcept;
iterator(const iterator&) = delete;
iterator(iterator&&) = default;
iterator& operator=(const iterator&) = delete;
iterator& operator=(iterator&&) = default;
iterator& operator++();
void operator++(int);
Val& operator*() const;
friend bool operator==(const iterator& x, default_sentinel_t);
private:
basic_istream_view* parent_; // exposition only
};
}
Class template std::ranges::ref_view
namespace std::ranges {
template<range R>
requires is_object_v<R>
class ref_view : public view_interface<ref_view<R>> {
private:
R* r_; // exposition only
public:
template</*different-from*/<ref_view> T>
requires /* see description */
constexpr ref_view(T&& t);
constexpr R& base() const { return *r_; }
constexpr iterator_t<R> begin() const { return ranges::begin(*r_); }
constexpr sentinel_t<R> end() const { return ranges::end(*r_); }
constexpr bool empty() const
requires requires { ranges::empty(*r_); }
{ return ranges::empty(*r_); }
constexpr auto size() const requires sized_range<R>
{ return ranges::size(*r_); }
constexpr auto data() const requires contiguous_range<R>
{ return ranges::data(*r_); }
};
template<class R>
ref_view(R&) -> ref_view<R>;
}
Class template std::ranges::owning_view
namespace std::ranges {
template<range R>
requires movable<R> && (!/*is-initializer-list*/<R>)
class owning_view : public view_interface<owning_view<R>> {
private:
R r_ = R(); // exposition only
public:
owning_view() requires default_initializable<R> = default;
constexpr owning_view(R&& t);
owning_view(owning_view&&) = default;
owning_view& operator=(owning_view&&) = default;
constexpr R& base() & noexcept { return r_; }
constexpr const R& base() const& noexcept { return r_; }
constexpr R&& base() && noexcept { return std::move(r_); }
constexpr const R&& base() const&& noexcept { return std::move(r_); }
constexpr iterator_t<R> begin() { return ranges::begin(r_); }
constexpr sentinel_t<R> end() { return ranges::end(r_); }
constexpr auto begin() const requires range<const R>
{ return ranges::begin(r_); }
constexpr auto end() const requires range<const R>
{ return ranges::end(r_); }
constexpr bool empty() requires requires { ranges::empty(r_); }
{ return ranges::empty(r_); }
constexpr bool empty() const requires requires { ranges::empty(r_); }
{ return ranges::empty(r_); }
constexpr auto size() requires sized_range<R>
{ return ranges::size(r_); }
constexpr auto size() const requires sized_range<const R>
{ return ranges::size(r_); }
constexpr auto data() requires contiguous_range<R>
{ return ranges::data(r_); }
constexpr auto data() const requires contiguous_range<const R>
{ return ranges::data(r_); }
};
}
Class template std::ranges::filter_view
namespace std::ranges {
template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class filter_view : public view_interface<filter_view<V, Pred>> {
private:
V base_ = V(); // exposition only
/*copyable-box*/<Pred> pred_; // exposition only
// class filter_view::iterator
class iterator; // exposition only
// class filter_view::sentinel
class sentinel; // exposition only
public:
filter_view() requires default_initializable<V> &&
default_initializable<Pred> = default;
constexpr filter_view(V base, Pred pred);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr const Pred& pred() const;
constexpr iterator begin();
constexpr auto end() {
if constexpr (common_range<V>)
return iterator{*this, ranges::end(base_)};
else
return sentinel{*this};
}
};
template<class R, class Pred>
filter_view(R&&, Pred) -> filter_view<views::all_t<R>, Pred>;
}
Class std::ranges::filter_view::iterator
namespace std::ranges {
template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class filter_view<V, Pred>::iterator {
private:
iterator_t<V> current_ = iterator_t<V>(); // exposition only
filter_view* parent_ = nullptr; // exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = /* see description */; // not always present
using value_type = range_value_t<V>;
using difference_type = range_difference_t<V>;
iterator() requires default_initializable<iterator_t<V>> = default;
constexpr iterator(filter_view& parent, iterator_t<V> current);
constexpr const iterator_t<V>& base() const & noexcept;
constexpr iterator_t<V> base() &&;
constexpr range_reference_t<V> operator*() const;
constexpr iterator_t<V> operator->() const
requires /*has-arrow*/<iterator_t<V>> && copyable<iterator_t<V>>;
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires forward_range<V>;
constexpr iterator& operator--() requires bidirectional_range<V>;
constexpr iterator operator--(int) requires bidirectional_range<V>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires equality_comparable<iterator_t<V>>;
friend constexpr range_rvalue_reference_t<V> iter_move(const iterator& i)
noexcept(noexcept(ranges::iter_move(i.current_)));
friend constexpr void iter_swap(const iterator& x, const iterator& y)
noexcept(noexcept(ranges::iter_swap(x.current_, y.current_)))
requires indirectly_swappable<iterator_t<V>>;
};
}
Class std::ranges::filter_view::sentinel
namespace std::ranges {
template<input_range V, indirect_unary_predicate<iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class filter_view<V, Pred>::sentinel {
private:
sentinel_t<V> end_ = sentinel_t<V>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(filter_view& parent);
constexpr sentinel_t<V> base() const;
friend constexpr bool operator==(const iterator& x, const sentinel& y);
};
}
Class template std::ranges::transform_view
namespace std::ranges {
template<input_range V, copy_constructible F>
requires view<V> && is_object_v<F> &&
regular_invocable<F&, range_reference_t<V>> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<V>>>
class transform_view : public view_interface<transform_view<V, F>> {
private:
// class template transform_view::iterator
template<bool> struct iterator; // exposition only
// class template transform_view::sentinel
template<bool> struct sentinel; // exposition only
V base_ = V(); // exposition only
/*copyable-box*/<F> fun_; // exposition only
public:
transform_view() requires default_initializable<V> &&
default_initializable<F> = default;
constexpr transform_view(V base, F fun);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr iterator<false> begin();
constexpr iterator<true> begin() const
requires range<const V> &&
regular_invocable<const F&, range_reference_t<const V>>;
constexpr sentinel<false> end();
constexpr iterator<false> end() requires common_range<V>;
constexpr sentinel<true> end() const
requires range<const V> &&
regular_invocable<const F&, range_reference_t<const V>>;
constexpr iterator<true> end() const
requires common_range<const V> &&
regular_invocable<const F&, range_reference_t<const V>>;
constexpr auto size() requires sized_range<V> { return ranges::size(base_); }
constexpr auto size() const requires sized_range<const V>
{ return ranges::size(base_); }
};
template<class R, class F>
transform_view(R&&, F) -> transform_view<views::all_t<R>, F>;
}
Class template std::ranges::transform_view::iterator
namespace std::ranges {
template<input_range V, copy_constructible F>
requires view<V> && is_object_v<F> &&
regular_invocable<F&, range_reference_t<V>> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<V>>>
template<bool Const>
class transform_view<V, F>::iterator {
private:
using Parent = /*maybe-const*/<Const, transform_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
iterator_t<Base> current_ = iterator_t<Base>(); // exposition only
Parent* parent_ = nullptr; // exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = /* see description */; // not always present
using value_type =
remove_cvref_t<invoke_result_t<F&, range_reference_t<Base>>>;
using difference_type = range_difference_t<Base>;
iterator() requires default_initializable<iterator_t<Base>> = default;
constexpr iterator(Parent& parent, iterator_t<Base> current);
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>;
constexpr const iterator_t<Base>& base() const & noexcept;
constexpr iterator_t<Base> base() &&;
constexpr decltype(auto) operator*() const {
return invoke(*parent_->fun_, *current_);
}
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires forward_range<Base>;
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type n)
requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type n)
requires random_access_range<Base>;
constexpr decltype(auto) operator[](difference_type n) const
requires random_access_range<Base> {
return invoke(*parent_->fun_, current_[n]);
}
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires equality_comparable<iterator_t<Base>>;
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> && three_way_comparable<iterator_t<Base>>;
friend constexpr iterator operator+(iterator i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, iterator i)
requires random_access_range<Base>;
friend constexpr iterator operator-(iterator i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>;
friend constexpr decltype(auto) iter_move(const iterator& i)
noexcept(noexcept(invoke(*i.parent_->fun_, *i.current_))) {
if constexpr (is_lvalue_reference_v<decltype(*i)>)
return std::move(*i);
else
return *i;
}
};
}
Class template std::ranges::transform_view::sentinel
namespace std::ranges {
template<input_range V, copy_constructible F>
requires view<V> && is_object_v<F> &&
regular_invocable<F&, range_reference_t<V>> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<V>>>
template<bool Const>
class transform_view<V, F>::sentinel {
private:
using Parent = /*maybe-const*/<Const, transform_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(sentinel_t<Base> end);
constexpr sentinel(sentinel<!Const> i)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
constexpr sentinel_t<Base> base() const;
template<bool OtherConst>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>,
iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>,
iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const sentinel& y, const iterator<OtherConst>& x);
};
}
Class template std::ranges::take_view
namespace std::ranges {
template<view V>
class take_view : public view_interface<take_view<V>> {
private:
V base_ = V(); // exposition only
range_difference_t<V> count_ = 0; // exposition only
// class template take_view::sentinel
template<bool> struct sentinel; // exposition only
public:
take_view() requires default_initializable<V> = default;
constexpr take_view(V base, range_difference_t<V> count);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() requires (!/*simple-view*/<V>) {
if constexpr (sized_range<V>) {
if constexpr (random_access_range<V>) {
return ranges::begin(base_);
} else {
auto sz = range_difference_t<V>(size());
return counted_iterator(ranges::begin(base_), sz);
}
} else {
return counted_iterator(ranges::begin(base_), count_);
}
}
constexpr auto begin() const requires range<const V> {
if constexpr (sized_range<const V>) {
if constexpr (random_access_range<const V>) {
return ranges::begin(base_);
} else {
auto sz = range_difference_t<const V>(size());
return counted_iterator(ranges::begin(base_), sz);
}
} else {
return counted_iterator(ranges::begin(base_), count_);
}
}
constexpr auto end() requires (!/*simple-view*/<V>) {
if constexpr (sized_range<V>) {
if constexpr (random_access_range<V>)
return ranges::begin(base_) + range_difference_t<V>(size());
else
return default_sentinel;
} else {
return sentinel<false>{ranges::end(base_)};
}
}
constexpr auto end() const requires range<const V> {
if constexpr (sized_range<const V>) {
if constexpr (random_access_range<const V>)
return ranges::begin(base_) + range_difference_t<const V>(size());
else
return default_sentinel;
} else {
return sentinel<true>{ranges::end(base_)};
}
}
constexpr auto size() requires sized_range<V> {
auto n = ranges::size(base_);
return ranges::min(n, static_cast<decltype(n)>(count_));
}
constexpr auto size() const requires sized_range<const V> {
auto n = ranges::size(base_);
return ranges::min(n, static_cast<decltype(n)>(count_));
}
};
template<class R>
take_view(R&&, range_difference_t<R>)
-> take_view<views::all_t<R>>;
}
Class template std::ranges::take_view::sentinel
namespace std::ranges {
template<view V>
template<bool Const>
class take_view<V>::sentinel {
private:
using Base = /*maybe-const*/<Const, V>; // exposition only
template<bool OtherConst>
using CI =
counted_iterator<iterator_t</*maybe-const*/<OtherConst, V>>>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(sentinel_t<Base> end);
constexpr sentinel(sentinel<!Const> s)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
constexpr sentinel_t<Base> base() const;
friend constexpr bool operator==(const CI<Const>& y, const sentinel& x);
template<bool OtherConst = !Const>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const CI<OtherConst>& y, const sentinel& x);
};
}
Class template std::ranges::take_while_view
namespace std::ranges {
template<view V, class Pred>
requires input_range<V> && is_object_v<Pred> &&
indirect_unary_predicate<const Pred, iterator_t<V>>
class take_while_view : public view_interface<take_while_view<V, Pred>> {
// class template take_while_view::sentinel
template<bool> class sentinel; // exposition only
V base_ = V(); // exposition only
/*copyable-box*/<Pred> pred_; // exposition only
public:
take_while_view() requires default_initializable<V> &&
default_initializable<Pred> = default;
constexpr take_while_view(V base, Pred pred);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr const Pred& pred() const;
constexpr auto begin() requires (!/*simple-view*/<V>)
{ return ranges::begin(base_); }
constexpr auto begin() const
requires range<const V> &&
indirect_unary_predicate<const Pred, iterator_t<const V>>
{ return ranges::begin(base_); }
constexpr auto end() requires (!/*simple-view*/<V>)
{ return sentinel<false>(ranges::end(base_), addressof(*pred_)); }
constexpr auto end() const
requires range<const V> &&
indirect_unary_predicate<const Pred, iterator_t<const V>>
{ return sentinel<true>(ranges::end(base_), addressof(*pred_)); }
};
template<class R, class Pred>
take_while_view(R&&, Pred) -> take_while_view<views::all_t<R>, Pred>;
}
Class template std::ranges::take_while_view::sentinel
namespace std::ranges {
template<view V, class Pred>
requires input_range<V> && is_object_v<Pred> &&
indirect_unary_predicate<const Pred, iterator_t<V>>
template<bool Const>
class take_while_view<V, Pred>::sentinel {
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
const Pred* pred_ = nullptr; // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(sentinel_t<Base> end, const Pred* pred);
constexpr sentinel(sentinel<!Const> s)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
constexpr sentinel_t<Base> base() const { return end_; }
friend constexpr bool operator==(const iterator_t<Base>& x, const sentinel& y);
template<bool OtherConst = !Const>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator_t</*maybe-const*/<OtherConst, V>>& x,
const sentinel& y);
};
}
Class template std::ranges::drop_view
namespace std::ranges {
template<view V>
class drop_view : public view_interface<drop_view<V>> {
public:
drop_view() requires default_initializable<V> = default;
constexpr drop_view(V base, range_difference_t<V> count);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin()
requires (!(/*simple-view*/<V> &&
random_access_range<const V> && sized_range<const V>));
constexpr auto begin() const
requires random_access_range<const V> && sized_range<const V>;
constexpr auto end() requires (!/*simple-view*/<V>)
{ return ranges::end(base_); }
constexpr auto end() const requires range<const V>
{ return ranges::end(base_); }
constexpr auto size() requires sized_range<V> {
const auto s = ranges::size(base_);
const auto c = static_cast<decltype(s)>(count_);
return s < c ? 0 : s - c;
}
constexpr auto size() const requires sized_range<const V> {
const auto s = ranges::size(base_);
const auto c = static_cast<decltype(s)>(count_);
return s < c ? 0 : s - c;
}
private:
V base_ = V(); // exposition only
range_difference_t<V> count_ = 0; // exposition only
};
template<class R>
drop_view(R&&, range_difference_t<R>) -> drop_view<views::all_t<R>>;
}
Class template std::ranges::drop_while_view
namespace std::ranges {
template<view V, class Pred>
requires input_range<V> && is_object_v<Pred> &&
indirect_unary_predicate<const Pred, iterator_t<V>>
class drop_while_view : public view_interface<drop_while_view<V, Pred>> {
public:
drop_while_view() requires default_initializable<V> &&
default_initializable<Pred> = default;
constexpr drop_while_view(V base, Pred pred);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr const Pred& pred() const;
constexpr auto begin();
constexpr auto end() { return ranges::end(base_); }
private:
V base_ = V(); // exposition only
/*copyable-box*/<Pred> pred_; // exposition only
};
template<class R, class Pred>
drop_while_view(R&&, Pred) -> drop_while_view<views::all_t<R>, Pred>;
}
Class template std::ranges::join_view
namespace std::ranges {
template<input_range V>
requires view<V> && input_range<range_reference_t<V>>
class join_view : public view_interface<join_view<V>> {
private:
using InnerRng = range_reference_t<V>; // exposition only
// class template join_view::iterator
template<bool Const>
struct iterator; // exposition only
// class template join_view::sentinel
template<bool Const>
struct sentinel; // exposition only
V base_ = V(); // exposition only
/*non-propagating-cache*/<remove_cv_t<InnerRng>>inner_;
// exposition only, present only when !is_reference_v<InnerRng>
public:
join_view() requires default_initializable<V> = default;
constexpr explicit join_view(V base);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() {
constexpr bool use_const = /*simple-view*/<V> &&
is_reference_v<range_reference_t<V>>;
return iterator<use_const>{*this, ranges::begin(base_)};
}
constexpr auto begin() const
requires input_range<const V> &&
is_reference_v<range_reference_t<const V>>
{ return iterator<true>{*this, ranges::begin(base_)}; }
constexpr auto end() {
if constexpr (forward_range<V> &&
is_reference_v<InnerRng> && forward_range<InnerRng> &&
common_range<V> && common_range<InnerRng>)
return iterator</*simple-view*/<V>>{*this, ranges::end(base_)};
else
return sentinel</*simple-view*/<V>>{*this};
}
constexpr auto end() const
requires input_range<const V> &&
is_reference_v<range_reference_t<const V>> {
if constexpr (forward_range<const V> &&
forward_range<range_reference_t<const V>> &&
common_range<const V> &&
common_range<range_reference_t<const V>>)
return iterator<true>{*this, ranges::end(base_)};
else
return sentinel<true>{*this};
}
};
template<class R>
explicit join_view(R&&) -> join_view<views::all_t<R>>;
}
Class template std::ranges::join_view::iterator
namespace std::ranges {
template<input_range V>
requires view<V> && input_range<range_reference_t<V>>
template<bool Const>
struct join_view<V>::iterator {
private:
using Parent = /*maybe-const*/<Const, join_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
using OuterIter = iterator_t<Base>; // exposition only
using InnerIter = iterator_t<range_reference_t<Base>>; // exposition only
static constexpr bool /*ref-is-glvalue*/ = // exposition only
is_reference_v<range_reference_t<Base>>;
OuterIter outer_ = OuterIter(); // exposition only
InnerIter inner_ = InnerIter(); // exposition only
Parent* parent_ = nullptr; // exposition only
constexpr void satisfy(); // exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = /* see description */; // not always present
using value_type = range_value_t<range_reference_t<Base>>;
using difference_type = /* see description */;
iterator() requires default_initializable<OuterIter> &&
default_initializable<InnerIter> = default;
constexpr iterator(Parent& parent, OuterIter outer);
constexpr iterator(iterator<!Const> i)
requires Const &&
convertible_to<iterator_t<V>, OuterIter> &&
convertible_to<iterator_t<InnerRng>, InnerIter>;
constexpr decltype(auto) operator*() const { return *inner_; }
constexpr InnerIter operator->() const
requires /*has-arrow*/<InnerIter> && copyable<InnerIter>;
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int)
requires /*ref-is-glvalue*/ && forward_range<Base> &&
forward_range<range_reference_t<Base>>;
constexpr iterator& operator--()
requires /*ref-is-glvalue*/ && bidirectional_range<Base> &&
bidirectional_range<range_reference_t<Base>> &&
common_range<range_reference_t<Base>>;
constexpr iterator operator--(int)
requires /*ref-is-glvalue*/ && bidirectional_range<Base> &&
bidirectional_range<range_reference_t<Base>> &&
common_range<range_reference_t<Base>>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires /*ref-is-glvalue*/ && equality_comparable<iterator_t<Base>> &&
equality_comparable<iterator_t<range_reference_t<Base>>>;
friend constexpr decltype(auto) iter_move(const iterator& i)
noexcept(noexcept(ranges::iter_move(i.inner_))) {
return ranges::iter_move(i.inner_);
}
friend constexpr void iter_swap(const iterator& x, const iterator& y)
noexcept(noexcept(ranges::iter_swap(x.inner_, y.inner_)))
requires indirectly_swappable<InnerIter>;
};
}
Class template std::ranges::join_view::sentinel
namespace std::ranges {
template<input_range V>
requires view<V> && input_range<range_reference_t<V>>
template<bool Const>
struct join_view<V>::sentinel {
private:
using Parent = /*maybe-const*/<Const, join_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(Parent& parent);
constexpr sentinel(sentinel<!Const> s)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
template<bool OtherConst>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
};
}
Class template std::ranges::join_with_view
namespace std::ranges {
template<class R, class P>
concept /*compatible-joinable-ranges*/ = // exposition only
common_with<range_value_t<R>, range_value_t<P>> &&
common_reference_with<range_reference_t<R>, range_reference_t<P>> &&
common_reference_with<range_rvalue_reference_t<R>, range_rvalue_reference_t<P>>;
template<class R>
concept /*bidirectional-common*/ = // exposition only
bidirectional_range<R> && common_range<R>;
template<input_range V, forward_range Pattern>
requires view<V> && input_range<range_reference_t<V>>
&& view<Pattern>
&& /*compatible-joinable-ranges*/<range_reference_t<V>, Pattern>
class join_with_view : public view_interface<join_with_view<V, Pattern>> {
using InnerRng = range_reference_t<V>; // exposition only
V base_ = V(); // exposition only
// exposition only, present only when !is_reference_v<inner-rng>
/*non-propagating-cache*/<remove_cv_t<InnerRng>> inner_;
Pattern pattern_ = Pattern(); // exposition only
// class template join_with_view::iterator
template<bool Const> struct iterator; // exposition only
// class template join_with_view::sentinel
template<bool Const> struct sentinel; // exposition only
public:
join_with_view()
requires default_initializable<V> && default_initializable<Pattern> = default;
constexpr join_with_view(V base, Pattern pattern);
template<input_range R>
requires constructible_from<V, views::all_t<R>> &&
constructible_from<Pattern, single_view<range_value_t<InnerRng>>>
constexpr join_with_view(R&& r, range_value_t<InnerRng> e);
constexpr V base() const & requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() {
constexpr bool use_const =
/*simple-view*/<V>
&& is_reference_v<InnerRng>
&& /*simple-view*/<Pattern>;
return iterator<use_const>{*this, ranges::begin(base_)};
}
constexpr auto begin() const
requires input_range<const V> &&
forward_range<const Pattern> &&
is_reference_v<range_reference_t<const V>> {
return iterator<true>{*this, ranges::begin(base_)};
}
constexpr auto end() {
if constexpr (forward_range<V> &&
is_reference_v<InnerRng> && forward_range<InnerRng> &&
common_range<V> && common_range<InnerRng>)
return iterator</*simple-view*/<V> && /*simple-view*/<Pattern>>{
*this, ranges::end(base_)
};
else
return sentinel</*simple-view*/<V> && /*simple-view*/<Pattern>>{*this};
}
constexpr auto end() const
requires input_range<const V> && forward_range<const Pattern> &&
is_reference_v<range_reference_t<const V>> {
using InnerConstRng = range_reference_t<const V>;
if constexpr (forward_range<const V> && forward_range<InnerConstRng> &&
common_range<const V> && common_range<InnerConstRng>)
return iterator<true>{*this, ranges::end(base_)};
else
return sentinel<true>{*this};
}
};
template<class R, class P>
join_with_view(R&&, P&&) -> join_with_view<views::all_t<R>, views::all_t<P>>;
template<input_range R>
join_with_view(R&&, range_value_t<range_reference_t<R>>)
-> join_with_view<views::all_t<R>, single_view<range_value_t<range_reference_t<R>>>>;
}
Class template std::ranges::join_with_view::iterator
namespace std::ranges {
template<input_range V, forward_range Pattern>
requires view<V> && input_range<range_reference_t<V>>
&& view<Pattern> && /*compatible-joinable-ranges*/<range_reference_t<V>, Pattern>
template<bool Const>
class join_with_view<V, Pattern>::iterator {
using Parent = /*maybe-const*/<Const, join_with_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
using InnerBase = range_reference_t<Base>; // exposition only
using PatternBase = /*maybe-const*/<Const, Pattern>; // exposition only
using OuterIter = iterator_t<Base>; // exposition only
using InnerIter = iterator_t<InnerBase>; // exposition only
using PatternIter = iterator_t<PatternBase>; // exposition only
static constexpr bool /*ref-is-glvalue*/ = is_reference_v<InnerBase>; // exposition only
Parent* parent_ = nullptr; // exposition only
OuterIter outer_it_ = OuterIter(); // exposition only
variant<PatternIter, InnerIter> inner_it_; // exposition only
constexpr iterator(Parent& parent, iterator_t<Base> outer); // exposition only
constexpr auto&& /*update-inner*/(const OuterIter&); // exposition only
constexpr auto&& /*get-inner*/(const OuterIter&); // exposition only
constexpr void /*satisfy*/(); // exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = /* see description */; // not always present
using value_type = /* see description */;
using difference_type = /* see description */;
iterator() requires default_initializable<OuterIter> = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, OuterIter> &&
convertible_to<iterator_t<InnerRng>, InnerIter> &&
convertible_to<iterator_t<Pattern>, PatternIter>;
constexpr decltype(auto) operator*() const;
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int)
requires /*ref-is-glvalue*/ && forward_iterator<OuterIter> &&
forward_iterator<InnerIter>;
constexpr iterator& operator--()
requires /*ref-is-glvalue*/ && bidirectional_range<Base> &&
/*bidirectional-common*/<InnerBase> &&
/*bidirectional-common*/<PatternBase>;
constexpr iterator operator--(int)
requires /*ref-is-glvalue*/ && bidirectional_range<Base> &&
/*bidirectional-common*/<InnerBase> &&
/*bidirectional-common*/<PatternBase>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires /*ref-is-glvalue*/ && equality_comparable<OuterIter> &&
equality_comparable<InnerIter>;
friend constexpr decltype(auto) iter_move(const iterator& x) {
using rvalue_reference = common_reference_t<
iter_rvalue_reference_t<InnerIter>,
iter_rvalue_reference_t<PatternIter>>;
return visit<rvalue_reference>(ranges::iter_move, x.inner_it_);
}
friend constexpr void iter_swap(const iterator& x, const iterator& y)
requires indirectly_swappable<InnerIter, PatternIter> {
visit(ranges::iter_swap, x.inner_it_, y.inner_it_);
}
};
}
Class template std::ranges::join_with_view::sentinel
namespace std::ranges {
template<input_range V, forward_range Pattern>
requires view<V> && input_range<range_reference_t<V>>
&& view<Pattern> && /*compatible-joinable-ranges*/<range_reference_t<V>, Pattern>
template<bool Const>
class join_with_view<V, Pattern>::sentinel {
using Parent = /*maybe-const*/<Const, join_with_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
constexpr explicit sentinel(Parent& parent); // exposition only
public:
sentinel() = default;
constexpr sentinel(sentinel<!Const> s)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
template <bool OtherConst>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
};
}
Class template std::ranges::lazy_split_view
namespace std::ranges {
template<auto> struct /*require-constant*/; // exposition only
template<class R>
concept /*tiny-range*/ = // exposition only
sized_range<R> &&
requires { typename /*require-constant*/<remove_reference_t<R>::size()>; } &&
(remove_reference_t<R>::size() <= 1);
template<input_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
&& (forward_range<V> || /*tiny-range*/<Pattern>)
class lazy_split_view : public view_interface<lazy_split_view<V, Pattern>> {
private:
V base_ = V(); // exposition only
Pattern pattern_ = Pattern(); // exposition only
/*non-propagating-cache*/<iterator_t<V>> current_; // exposition only, present only
// if !forward_range<V>
// class template lazy_split_view::/*outer-iterator*/
template<bool> struct /*outer-iterator*/; // exposition only
// class template lazy_split_view::/*inner-iterator*/
template<bool> struct /*inner-iterator*/; // exposition only
public:
lazy_split_view()
requires default_initializable<V> && default_initializable<Pattern> = default;
constexpr lazy_split_view(V base, Pattern pattern);
template<input_range R>
requires constructible_from<V, views::all_t<R>> &&
constructible_from<Pattern, single_view<range_value_t<R>>>
constexpr lazy_split_view(R&& r, range_value_t<R> e);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() {
if constexpr (forward_range<V>) {
return /*outer-iterator*/</*simple-view*/<V> && /*simple-view*/<Pattern>>
{*this, ranges::begin(base_)};
} else {
current_ = ranges::begin(base_);
return /*outer-iterator*/<false>{*this};
}
}
constexpr auto begin() const requires forward_range<V> && forward_range<const V> {
return /*outer-iterator*/<true>{*this, ranges::begin(base_)};
}
constexpr auto end() requires forward_range<V> && common_range<V> {
return /*outer-iterator*/</*simple-view*/<V> && /*simple-view*/<Pattern>>
{*this, ranges::end(base_)};
}
constexpr auto end() const {
if constexpr (forward_range<V> && forward_range<const V> && common_range<const V>)
return /*outer-iterator*/<true>{*this, ranges::end(base_)};
else
return default_sentinel;
}
};
template<class R, class P>
lazy_split_view(R&&, P&&) -> lazy_split_view<views::all_t<R>, views::all_t<P>>;
template<input_range R>
lazy_split_view(R&&, range_value_t<R>)
-> lazy_split_view<views::all_t<R>, single_view<range_value_t<R>>>;
}
Class template std::ranges::lazy_split_view::outer_iterator
namespace std::ranges {
template<input_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
&& (forward_range<V> || /*tiny-range*/<Pattern>)
template<bool Const>
struct lazy_split_view<V, Pattern>::/*outer-iterator*/ {
private:
using Parent = /*maybe-const*/<Const, lazy_split_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
Parent* parent_ = nullptr; // exposition only
iterator_t<Base> current_ = iterator_t<Base>(); // exposition only, present only
// if V models forward_range
bool trailing_empty_ = false; // exposition only
public:
using iterator_concept =
conditional_t<forward_range<Base>, forward_iterator_tag, input_iterator_tag>;
using iterator_category = input_iterator_tag; // present only if Base
// models forward_range
// class lazy_split_view::/*outer-iterator*/::value_type
struct value_type;
using difference_type = range_difference_t<Base>;
/*outer-iterator*/() = default;
constexpr explicit /*outer-iterator*/(Parent& parent)
requires (!forward_range<Base>);
constexpr /*outer-iterator*/(Parent& parent, iterator_t<Base> current)
requires forward_range<Base>;
constexpr /*outer-iterator*/(/*outer-iterator*/<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>;
constexpr value_type operator*() const;
constexpr /*outer-iterator*/& operator++();
constexpr decltype(auto) operator++(int) {
if constexpr (forward_range<Base>) {
auto tmp = *this;
++*this;
return tmp;
} else
++*this;
}
friend constexpr bool operator==(const /*outer-iterator*/& x,
const /*outer-iterator*/& y)
requires forward_range<Base>;
friend constexpr bool operator==(const /*outer-iterator*/& x, default_sentinel_t);
};
}
Class std::ranges::lazy_split_view::outer_iterator::value_type
namespace std::ranges {
template<input_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
&& (forward_range<V> || /*tiny-range*/<Pattern>)
template<bool Const>
struct lazy_split_view<V, Pattern>::/*outer-iterator*/<Const>::value_type
: view_interface<value_type> {
private:
/*outer-iterator*/ i_ = /*outer-iterator*/(); // exposition only
public:
value_type() = default;
constexpr explicit value_type(/*outer-iterator*/ i);
constexpr /*inner-iterator*/<Const> begin() const;
constexpr default_sentinel_t end() const noexcept;
};
}
Class template std::ranges::lazy_split_view::inner_iterator
namespace std::ranges {
template<input_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
&& (forward_range<V> || /*tiny-range*/<Pattern>)
template<bool Const>
struct lazy_split_view<V, Pattern>::/*inner-iterator*/ {
private:
using Base = /*maybe-const*/<Const, V>; // exposition only
/*outer-iterator*/<Const> i_ = /*outer-iterator*/<Const>(); // exposition only
bool incremented_ = false; // exposition only
public:
using iterator_concept = typename /*outer-iterator*/<Const>::iterator_concept;
using iterator_category = /* see description */; // present only if Base
// models forward_range
using value_type = range_value_t<Base>;
using difference_type = range_difference_t<Base>;
/*inner-iterator*/() = default;
constexpr explicit /*inner-iterator*/(/*outer-iterator*/<Const> i);
constexpr const iterator_t<Base>& base() const & noexcept;
constexpr iterator_t<Base> base() && requires forward_range<V>;
constexpr decltype(auto) operator*() const { return *i_.current; }
constexpr /*inner-iterator*/& operator++();
constexpr decltype(auto) operator++(int) {
if constexpr (forward_range<Base>) {
auto tmp = *this;
++*this;
return tmp;
} else
++*this;
}
friend constexpr bool operator==(const /*inner-iterator*/& x,
const /*inner-iterator*/& y)
requires forward_range<Base>;
friend constexpr bool operator==(const /*inner-iterator*/& x, default_sentinel_t);
friend constexpr decltype(auto) iter_move(const /*inner-iterator*/& i)
noexcept(noexcept(ranges::iter_move(i.i_.current))) {
return ranges::iter_move(i.i_.current);
}
friend constexpr void iter_swap(const /*inner-iterator*/& x,
const /*inner-iterator*/& y)
noexcept(noexcept(ranges::iter_swap(x.i_.current, y.i_.current)))
requires indirectly_swappable<iterator_t<Base>>;
};
}
Class template std::ranges::split_view
namespace std::ranges {
template<forward_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
class split_view : public view_interface<split_view<V, Pattern>> {
private:
V base_ = V(); // exposition only
Pattern pattern_ = Pattern(); // exposition only
// class split_view::iterator
struct iterator; // exposition only
// class split_view::sentinel
struct sentinel; // exposition only
public:
split_view()
requires default_initializable<V> && default_initializable<Pattern> = default;
constexpr split_view(V base, Pattern pattern);
template<forward_range R>
requires constructible_from<V, views::all_t<R>> &&
constructible_from<Pattern, single_view<range_value_t<R>>>
constexpr split_view(R&& r, range_value_t<R> e);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr iterator begin();
constexpr auto end() {
if constexpr (common_range<V>) {
return iterator{*this, ranges::end(base_), {} };
} else {
return sentinel{*this};
}
}
constexpr subrange<iterator_t<V>> /*find-next*/(iterator_t<V>); // exposition only
};
template<class R, class P>
split_view(R&&, P&&) -> split_view<views::all_t<R>, views::all_t<P>>;
template<forward_range R>
split_view(R&&, range_value_t<R>)
-> split_view<views::all_t<R>, single_view<range_value_t<R>>>;
}
Class template std::ranges::split_view::iterator
namespace std::ranges {
template<forward_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
class split_view<V, Pattern>::iterator {
private:
split_view* parent_ = nullptr; // exposition only
iterator_t<V> cur_ = iterator_t<V>(); // exposition only
subrange<iterator_t<V>> next_ = subrange<iterator_t<V>>(); // exposition only
bool trailing_empty_ = false; // exposition only
public:
using iterator_concept = forward_iterator_tag;
using iterator_category = input_iterator_tag;
using value_type = subrange<iterator_t<V>>;
using difference_type = range_difference_t<V>;
iterator() = default;
constexpr iterator(split_view& parent, iterator_t<V> current,
subrange<iterator_t<V>> next);
constexpr iterator_t<V> base() const;
constexpr value_type operator*() const;
constexpr iterator& operator++();
constexpr iterator operator++(int);
friend constexpr bool operator==(const iterator& x, const iterator& y);
};
}
Class template std::ranges::split_view::sentinel
namespace std::ranges {
template<forward_range V, forward_range Pattern>
requires view<V> && view<Pattern> &&
indirectly_comparable<iterator_t<V>, iterator_t<Pattern>, ranges::equal_to>
struct split_view<V, Pattern>::sentinel {
private:
sentinel_t<V> end_ = sentinel_t<V>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(split_view& parent);
friend constexpr bool operator==(const iterator& x, const sentinel& y);
};
}
Class template std::ranges::common_view
namespace std::ranges {
template<view V>
requires (!common_range<V> && copyable<iterator_t<V>>)
class common_view : public view_interface<common_view<V>> {
private:
V base_ = V(); // exposition only
public:
common_view() requires default_initializable<V> = default;
constexpr explicit common_view(V r);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() {
if constexpr (random_access_range<V> && sized_range<V>)
return ranges::begin(base_);
else
return common_iterator<iterator_t<V>, sentinel_t<V>>(ranges::begin(base_));
}
constexpr auto begin() const requires range<const V> {
if constexpr (random_access_range<const V> && sized_range<const V>)
return ranges::begin(base_);
else
return common_iterator<iterator_t<const V>,
sentinel_t<const V>>(ranges::begin(base_));
}
constexpr auto end() {
if constexpr (random_access_range<V> && sized_range<V>)
return ranges::begin(base_) + ranges::size(base_);
else
return common_iterator<iterator_t<V>, sentinel_t<V>>(ranges::end(base_));
}
constexpr auto end() const requires range<const V> {
if constexpr (random_access_range<const V> && sized_range<const V>)
return ranges::begin(base_) + ranges::size(base_);
else
return common_iterator<iterator_t<const V>,
sentinel_t<const V>>(ranges::end(base_));
}
constexpr auto size() requires sized_range<V> {
return ranges::size(base_);
}
constexpr auto size() const requires sized_range<const V> {
return ranges::size(base_);
}
};
template<class R>
common_view(R&&) -> common_view<views::all_t<R>>;
}
Class template std::ranges::reverse_view
namespace std::ranges {
template<view V>
requires bidirectional_range<V>
class reverse_view : public view_interface<reverse_view<V>> {
private:
V base_ = V(); // exposition only
public:
reverse_view() requires default_initializable<V> = default;
constexpr explicit reverse_view(V r);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr reverse_iterator<iterator_t<V>> begin();
constexpr reverse_iterator<iterator_t<V>> begin() requires common_range<V>;
constexpr auto begin() const requires common_range<const V>;
constexpr reverse_iterator<iterator_t<V>> end();
constexpr auto end() const requires common_range<const V>;
constexpr auto size() requires sized_range<V> {
return ranges::size(base_);
}
constexpr auto size() const requires sized_range<const V> {
return ranges::size(base_);
}
};
template<class R>
reverse_view(R&&) -> reverse_view<views::all_t<R>>;
}
Class template std::ranges::elements_view
namespace std::ranges {
template<class T, size_t N>
concept /*has-tuple-element*/ = // exposition only
requires(T t) {
typename tuple_size<T>::type;
requires N < tuple_size_v<T>;
typename tuple_element_t<N, T>;
{ std::get<N>(t) } -> convertible_to<const tuple_element_t<N, T>&>;
};
template<class T, size_t N>
concept /*returnable-element*/ = // exposition only
is_reference_v<T> || move_constructible<tuple_element_t<N, T>>;
template<input_range V, size_t N>
requires view<V> && /*has-tuple-element*/<range_value_t<V>, N> &&
/*has-tuple-element*/<remove_reference_t<range_reference_t<V>>, N> &&
/*returnable-element*/<range_reference_t<V>, N>
class elements_view : public view_interface<elements_view<V, N>> {
public:
elements_view() requires default_initializable<V> = default;
constexpr explicit elements_view(V base);
constexpr V base() const& requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() requires (!/*simple-view*/<V>)
{ return iterator<false>(ranges::begin(base_)); }
constexpr auto begin() const requires range<const V>
{ return iterator<true>(ranges::begin(base_)); }
constexpr auto end() requires (!/*simple-view*/<V> && !common_range<V>)
{ return sentinel<false>{ranges::end(base_)}; }
constexpr auto end() requires (!/*simple-view*/<V> && common_range<V>)
{ return iterator<false>{ranges::end(base_)}; }
constexpr auto end() const requires range<const V>
{ return sentinel<true>{ranges::end(base_)}; }
constexpr auto end() const requires common_range<const V>
{ return iterator<true>{ranges::end(base_)}; }
constexpr auto size() requires sized_range<V>
{ return ranges::size(base_); }
constexpr auto size() const requires sized_range<const V>
{ return ranges::size(base_); }
private:
// class template elements_view::iterator
template<bool> struct iterator; // exposition only
// class template elements_view::sentinel
template<bool> struct sentinel; // exposition only
V base_ = V(); // exposition only
};
}
Class template std::ranges::elements_view::iterator
namespace std::ranges {
template<input_range V, size_t N>
requires view<V> && /*has-tuple-element*/<range_value_t<V>, N> &&
/*has-tuple-element*/<remove_reference_t<range_reference_t<V>>, N> &&
/*returnable-element*/<range_reference_t<V>, N>
template<bool Const>
class elements_view<V, N>::iterator {
using Base = /*maybe-const*/<Const, V>; // exposition only
iterator_t<Base> current_ = iterator_t<Base>(); // exposition only
static constexpr decltype(auto) /*get-element*/(const iterator_t<Base>& i);
// exposition only
public:
using iterator_concept = /* see description */;
using iterator_category = /* see description */; // not always present
using value_type = remove_cvref_t<tuple_element_t<N, range_value_t<Base>>>;
using difference_type = range_difference_t<Base>;
iterator() requires default_initializable<iterator_t<Base>> = default;
constexpr explicit iterator(iterator_t<Base> current);
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>;
constexpr const iterator_t<Base>& base() const & noexcept;
constexpr iterator_t<Base> base() &&;
constexpr decltype(auto) operator*() const
{ return /*get-element*/(current_); }
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires forward_range<Base>;
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x)
requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x)
requires random_access_range<Base>;
constexpr decltype(auto) operator[](difference_type n) const
requires random_access_range<Base>
{ return /*get-element*/(current_ + n); }
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires equality_comparable<iterator_t<Base>>;
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> && three_way_comparable<iterator_t<Base>>;
friend constexpr iterator operator+(const iterator& x, difference_type y)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type x, const iterator& y)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& x, difference_type y)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>;
};
}
Class template std::ranges::elements_view::sentinel
namespace std::ranges {
template<input_range V, size_t N>
requires view<V> && /*has-tuple-element*/<range_value_t<V>, N> &&
/*has-tuple-element*/<remove_reference_t<range_reference_t<V>>, N> &&
/*returnable-element*/<range_reference_t<V>, N>
template<bool Const>
class elements_view<V, N>::sentinel {
private:
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
public:
sentinel() = default;
constexpr explicit sentinel(sentinel_t<Base> end);
constexpr sentinel(sentinel<!Const> other)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
constexpr sentinel_t<Base> base() const;
template<bool OtherConst>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>,
iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>,
iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const sentinel& x, const iterator<OtherConst>& y);
};
}
Class template std::ranges::zip_view
namespace std::ranges {
template<class... Rs>
concept /*zip-is-common*/ = // exposition only
(sizeof...(Rs) == 1 && (common_range<Rs> && ...)) ||
(!(bidirectional_range<Rs> && ...) && (common_range<Rs> && ...)) ||
((random_access_range<Rs> && ...) && (sized_range<Rs> && ...));
template<class... Ts>
using /*tuple-or-pair*/ = /* see description */; // exposition only
template<class F, class Tuple>
constexpr auto /*tuple-transform*/(F&& f, Tuple&& tuple) { // exposition only
return apply([&]<class... Ts>(Ts&&... elements) {
return /*tuple-or-pair*/<invoke_result_t<F&, Ts>...>(
invoke(f, std::forward<Ts>(elements))...
);
}, std::forward<Tuple>(tuple));
}
template<class F, class Tuple>
constexpr void /*tuple-for-each*/(F&& f, Tuple&& tuple) { // exposition only
apply([&]<class... Ts>(Ts&&... elements) {
(invoke(f, std::forward<Ts>(elements)), ...);
}, std::forward<Tuple>(tuple));
}
template<input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0)
class zip_view : public view_interface<zip_view<Views...>> {
tuple<Views...> views_; // exposition only
// class template zip_view::iterator
template<bool> class iterator; // exposition only
// class template zip_view::sentinel
template<bool> class sentinel; // exposition only
public:
zip_view() = default;
constexpr explicit zip_view(Views... views);
constexpr auto begin() requires (!(/*simple-view*/<Views> && ...)) {
return iterator<false>(/*tuple-transform*/(ranges::begin, views_));
}
constexpr auto begin() const requires (range<const Views> && ...) {
return iterator<true>(/*tuple-transform*/(ranges::begin, views_));
}
constexpr auto end() requires (!(/*simple-view*/<Views> && ...)) {
if constexpr (!/*zip-is-common*/<Views...>) {
return sentinel<false>(/*tuple-transform*/(ranges::end, views_));
} else if constexpr ((random_access_range<Views> && ...)) {
return begin() + iter_difference_t<iterator<false>>(size());
} else {
return iterator<false>(/*tuple-transform*/(ranges::end, views_));
}
}
constexpr auto end() const requires (range<const Views> && ...) {
if constexpr (!/*zip-is-common*/<const Views...>) {
return sentinel<true>(/*tuple-transform*/(ranges::end, views_));
} else if constexpr ((random_access_range<const Views> && ...)) {
return begin() + iter_difference_t<iterator<true>>(size());
} else {
return iterator<true>(/*tuple-transform*/(ranges::end, views_));
}
}
constexpr auto size() requires (sized_range<Views> && ...);
constexpr auto size() const requires (sized_range<const Views> && ...);
};
template<class... Rs>
zip_view(Rs&&...) -> zip_view<views::all_t<Rs>...>;
}
Class template std::ranges::zip_view::iterator
namespace std::ranges {
template<bool Const, class... Views>
concept /*all-random-access*/ = // exposition only
(random_access_range</*maybe-const*/<Const, Views>> && ...);
template<bool Const, class... Views>
concept /*all-bidirectional*/ = // exposition only
(bidirectional_range</*maybe-const*/<Const, Views>> && ...);
template<bool Const, class... Views>
concept /*all-forward*/ = // exposition only
(forward_range</*maybe-const*/<Const, Views>> && ...);
template<input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0)
template<bool Const>
class zip_view<Views...>::iterator {
/*tuple-or-pair*/<iterator_t</*maybe-const*/<Const, Views>>...>
current_; // exposition only
constexpr explicit iterator(/*tuple-or-pair*/<iterator_t<
/*maybe-const*/<Const, Views>>...>); // exposition only
public:
using iterator_category = input_iterator_tag; // not always present
using iterator_concept = /* see description */;
using value_type = /*tuple-or-pair*/<range_value_t<
/*maybe-const*/<Const, Views>>...>;
using difference_type = common_type_t<range_difference_t<
/*maybe-const*/<Const, Views>>...>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && (convertible_to<iterator_t<Views>,
iterator_t</*maybe-const*/<Const, Views>>> && ...);
constexpr auto operator*() const;
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires /*all-forward*/<Const, Views...>;
constexpr iterator& operator--() requires /*all-bidirectional*/<Const, Views...>;
constexpr iterator operator--(int) requires /*all-bidirectional*/<Const, Views...>;
constexpr iterator& operator+=(difference_type x)
requires /*all-random-access*/<Const, Views...>;
constexpr iterator& operator-=(difference_type x)
requires /*all-random-access*/<Const, Views...>;
constexpr auto operator[](difference_type n) const
requires /*all-random-access*/<Const, Views...>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires (equality_comparable<iterator_t</*maybe-const*/<Const, Views>>> && ...);
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires /*all-random-access*/<Const, Views...>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires /*all-random-access*/<Const, Views...>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires /*all-random-access*/<Const, Views...>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires /*all-random-access*/<Const, Views...>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires /*all-random-access*/<Const, Views...> &&
(three_way_comparable<iterator_t</*maybe-const*/<Const, Views>>> && ...);
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires /*all-random-access*/<Const, Views...>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires /*all-random-access*/<Const, Views...>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires /*all-random-access*/<Const, Views...>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires (sized_sentinel_for<iterator_t</*maybe-const*/<Const, Views>>,
iterator_t</*maybe-const*/<Const, Views>>> && ...);
friend constexpr auto iter_move(const iterator& i) noexcept(/* see description */);
friend constexpr void iter_swap(const iterator& l, const iterator& r)
noexcept(/* see description */)
requires (indirectly_swappable<iterator_t</*maybe-const*/<Const, Views>>> && ...);
};
}
Class template std::ranges::zip_view::sentinel
namespace std::ranges {
template<input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0)
template<bool Const>
class zip_view<Views...>::sentinel {
/*tuple-or-pair*/<sentinel_t</*maybe-const*/<Const, Views>>...>
end_; // exposition only
constexpr explicit sentinel(/*tuple-or-pair*/<sentinel_t<
/*maybe-const*/<Const, Views>>...> end); // exposition only
public:
sentinel() = default;
constexpr sentinel(sentinel<!Const> i)
requires Const &&
(convertible_to<sentinel_t<Views>, sentinel_t<
/*maybe-const*/<Const, Views>>> && ...);
template<bool OtherConst>
requires (sentinel_for<sentinel_t</*maybe-const*/<Const, Views>>,
iterator_t</*maybe-const*/<OtherConst, Views>>> && ...)
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires (sized_sentinel_for<sentinel_t</*maybe-const*/<Const, Views>>,
iterator_t</*maybe-const*/<OtherConst, Views>>> && ...)
friend constexpr common_type_t<range_difference_t<
/*maybe-const*/<OtherConst, Views>>...>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires (sized_sentinel_for<sentinel_t</*maybe-const*/<Const, Views>>,
iterator_t</*maybe-const*/<OtherConst, Views>>> && ...)
friend constexpr common_type_t<range_difference_t<
/*maybe-const*/<OtherConst, Views>>...>
operator-(const sentinel& y, const iterator<OtherConst>& x);
};
}
Class template std::ranges::zip_transform_view
namespace std::ranges {
template<copy_constructible F, input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0) && is_object_v<F> &&
regular_invocable<F&, range_reference_t<Views>...> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<Views>...>>
class zip_transform_view : public view_interface<zip_transform_view<F, Views...>> {
/*copyable-box*/<F> fun_; // exposition only
zip_view<Views...> zip_; // exposition only
using InnerView = zip_view<Views...>; // exposition only
template<bool Const>
using ziperator = iterator_t</*maybe-const*/<Const, InnerView>>; // exposition only
template<bool Const>
using zentinel = sentinel_t</*maybe-const*/<Const, InnerView>>; // exposition only
// class template zip_transform_view::iterator
template<bool> class iterator; // exposition only
// class template zip_transform_view::sentinel
template<bool> class sentinel; // exposition only
public:
zip_transform_view() = default;
constexpr explicit zip_transform_view(F fun, Views... views);
constexpr auto begin() { return iterator<false>(*this, zip_.begin()); }
constexpr auto begin() const
requires range<const InnerView> &&
regular_invocable<const F&, range_reference_t<const Views>...> {
return iterator<true>(*this, zip_.begin());
}
constexpr auto end() {
if constexpr (common_range<InnerView>) {
return iterator<false>(*this, zip_.end());
} else {
return sentinel<false>(zip_.end());
}
}
constexpr auto end() const
requires range<const InnerView> &&
regular_invocable<const F&, range_reference_t<const Views>...> {
if constexpr (common_range<const InnerView>) {
return iterator<true>(*this, zip_.end());
} else {
return sentinel<true>(zip_.end());
}
}
constexpr auto size() requires sized_range<InnerView> {
return zip_.size();
}
constexpr auto size() const requires sized_range<const InnerView> {
return zip_.size();
}
};
template<class F, class... Rs>
zip_transform_view(F, Rs&&...) -> zip_transform_view<F, views::all_t<Rs>...>;
}
Class template std::ranges::zip_transform_view::iterator
namespace std::ranges {
template<copy_constructible F, input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0) && is_object_v<F> &&
regular_invocable<F&, range_reference_t<Views>...> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<Views>...>>
template<bool Const>
class zip_transform_view<F, Views...>::iterator {
using Parent = /*maybe-const*/<Const, zip_transform_view>; // exposition only
using Base = /*maybe-const*/<Const, InnerView>; // exposition only
Parent* parent_ = nullptr; // exposition only
ziperator<Const> inner_; // exposition only
constexpr iterator(Parent& parent, ziperator<Const> inner); // exposition only
public:
using iterator_category = /* see description */; // not always present
using iterator_concept = typename ziperator<Const>::iterator_concept;
using value_type =
remove_cvref_t<invoke_result_t</*maybe-const*/<Const, F>&,
range_reference_t<
/*maybe-const*/<Const, Views>>...>>;
using difference_type = range_difference_t<Base>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<ziperator<false>, ziperator<Const>>;
constexpr decltype(auto) operator*() const noexcept(/* see description */);
constexpr iterator& operator++();
constexpr void operator++(int);
constexpr iterator operator++(int) requires forward_range<Base>;
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x) requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x) requires random_access_range<Base>;
constexpr decltype(auto) operator[](difference_type n) const
requires random_access_range<Base>;
friend constexpr bool operator==(const iterator& x, const iterator& y)
requires equality_comparable<ziperator<Const>>;
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> && three_way_comparable<ziperator<Const>>;
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<ziperator<Const>, ziperator<Const>>;
};
}
Class template std::ranges::zip_transform_view::sentinel
namespace std::ranges {
template<copy_constructible F, input_range... Views>
requires (view<Views> && ...) && (sizeof...(Views) > 0) && is_object_v<F> &&
regular_invocable<F&, range_reference_t<Views>...> &&
/*can-reference*/<invoke_result_t<F&, range_reference_t<Views>...>>
template<bool Const>
class zip_transform_view<F, Views...>::sentinel {
zentinel<Const> inner_; // exposition only
constexpr explicit sentinel(zentinel<Const> inner); // exposition only
public:
sentinel() = default;
constexpr sentinel(sentinel<!Const> i)
requires Const && convertible_to<zentinel<false>, zentinel<Const>>;
template<bool OtherConst>
requires sentinel_for<zentinel<Const>, ziperator<OtherConst>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<zentinel<Const>, ziperator<OtherConst>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, InnerView>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<zentinel<Const>, ziperator<OtherConst>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, InnerView>>
operator-(const sentinel& x, const iterator<OtherConst>& y);
};
}
Class template std::ranges::adjacent_view
namespace std::ranges {
template<forward_range V, size_t N>
requires view<V> && (N > 0)
class adjacent_view : public view_interface<adjacent_view<V, N>> {
V base_ = V(); // exposition only
// class template adjacent_view::iterator
template<bool> class iterator; // exposition only
// class template adjacent_view::sentinel
template<bool> class sentinel; // exposition only
struct /*as-sentinel*/{}; // exposition only
public:
adjacent_view() requires default_initializable<V> = default;
constexpr explicit adjacent_view(V base);
constexpr auto begin() requires (!/*simple-view*/<V>) {
return iterator<false>(ranges::begin(base_), ranges::end(base_));
}
constexpr auto begin() const requires range<const V> {
return iterator<true>(ranges::begin(base_), ranges::end(base_));
}
constexpr auto end() requires (!/*simple-view*/<V>) {
if constexpr (common_range<V>) {
return iterator<false>(/*as-sentinel*/{}, ranges::begin(base_),
ranges::end(base_));
} else {
return sentinel<false>(ranges::end(base_));
}
}
constexpr auto end() const requires range<const V> {
if constexpr (common_range<const V>) {
return iterator<true>(/*as-sentinel*/{}, ranges::begin(base_),
ranges::end(base_));
} else {
return sentinel<true>(ranges::end(base_));
}
}
constexpr auto size() requires sized_range<V>;
constexpr auto size() const requires sized_range<const V>;
};
}
Class template std::ranges::adjacent_view::iterator
namespace std::ranges {
template<forward_range V, size_t N>
requires view<V> && (N > 0)
template<bool Const>
class adjacent_view<V, N>::iterator {
using Base = /*maybe-const*/<Const, V>; // exposition only
array<iterator_t<Base>, N> current_ = array<iterator_t<Base>, N>(); // exposition only
constexpr iterator(iterator_t<Base> first, sentinel_t<Base> last); // exposition only
constexpr iterator(/*as-sentinel*/, iterator_t<Base> first, iterator_t<Base> last);
// exposition only
public:
using iterator_category = input_iterator_tag;
using iterator_concept = /* see description */;
using value_type = /*tuple-or-pair*/</*REPEAT*/(range_value_t<Base>, N)...>;
using difference_type = range_difference_t<Base>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>;
constexpr auto operator*() const;
constexpr iterator& operator++();
constexpr iterator operator++(int);
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x)
requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x)
requires random_access_range<Base>;
constexpr auto operator[](difference_type n) const
requires random_access_range<Base>;
friend constexpr bool operator==(const iterator& x, const iterator& y);
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> &&
three_way_comparable<iterator_t<Base>>;
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>;
friend constexpr auto iter_move(const iterator& i) noexcept(/* see description */);
friend constexpr void iter_swap(const iterator& l, const iterator& r)
noexcept(/* see description */)
requires indirectly_swappable<iterator_t<Base>>;
};
}
Class template std::ranges::adjacent_view::sentinel
namespace std::ranges {
template<forward_range V, size_t N>
requires view<V> && (N > 0)
template<bool Const>
class adjacent_view<V, N>::sentinel {
using Base = /*maybe-const*/<Const, V>; // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
constexpr explicit sentinel(sentinel_t<Base> end); // exposition only
public:
sentinel() = default;
constexpr sentinel(sentinel<!Const> i)
requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
template<bool OtherConst>
requires sentinel_for<sentinel_t<Base>, iterator_t</*maybe-const*/<OtherConst, V>>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>, iterator_t<
/*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for<sentinel_t<Base>, iterator_t<
/*maybe-const*/<OtherConst, V>>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, V>>
operator-(const sentinel& y, const iterator<OtherConst>& x);
};
}
Class template std::ranges::adjacent_transform_view
namespace std::ranges {
template<forward_range V, copy_constructible F, size_t N>
requires view<V> && (N > 0) && is_object_v<F> &&
regular_invocable<F&, /*REPEAT*/(range_reference_t<V>, N)...> &&
/*can-reference*/<invoke_result_t<F&, /*REPEAT*/(range_reference_t<V>, N)...>>
class adjacent_transform_view :
public view_interface<adjacent_transform_view<V, F, N>> {
/*copyable-box*/<F> fun_; // exposition only
adjacent_view<V, N> inner_; // exposition only
using InnerView = adjacent_view<V, N>; // exposition only
template<bool Const>
using /*inner-iterator*/ =
iterator_t</*maybe-const*/<Const, InnerView>>; // exposition only
template<bool Const>
using /*inner-sentinel*/ =
sentinel_t</*maybe-const*/<Const, InnerView>>; // exposition only
// class template adjacent_transform_view::iterator
template<bool> class iterator; // exposition only
// class template adjacent_transform_view::sentinel
template<bool> class sentinel; // exposition only
public:
adjacent_transform_view() = default;
constexpr explicit adjacent_transform_view(V base, F fun);
constexpr auto begin() {
return iterator<false>(*this, inner_.begin());
}
constexpr auto begin() const
requires range<const InnerView> &&
regular_invocable<const F&, /*REPEAT*/(range_reference_t<const V>, N)...> {
return iterator<true>(*this, inner_.begin());
}
constexpr auto end() {
if constexpr (common_range<InnerView>) {
return iterator<false>(*this, inner_.end());
} else {
return sentinel<false>(inner_.end());
}
}
constexpr auto end() const
requires range<const InnerView> &&
regular_invocable<const F&, /*REPEAT*/(range_reference_t<const V>, N)...> {
if constexpr (common_range<const InnerView>) {
return iterator<true>(*this, inner_.end());
} else {
return sentinel<true>(inner_.end());
}
}
constexpr auto size() requires sized_range<InnerView> {
return inner_.size();
}
constexpr auto size() const requires sized_range<const InnerView> {
return inner_.size();
}
};
}
Class template std::ranges::adjacent_transform_view::iterator
namespace std::ranges {
template<forward_range V, copy_constructible F, size_t N>
requires view<V> && (N > 0) && is_object_v<F> &&
regular_invocable<F&, /*REPEAT*/(range_reference_t<V>, N)...> &&
/*can-reference*/<invoke_result_t<F&,
/*REPEAT*/(range_reference_t<V>, N)...>>
template<bool Const>
class adjacent_transform_view<F, V...>::iterator {
using Parent = /*maybe-const*/<Const, adjacent_transform_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
Parent* parent_ = nullptr; // exposition only
/*inner-iterator*/<Const> inner_; // exposition only
constexpr iterator(Parent& parent,
/*inner-iterator*/<Const> inner); // exposition only
public:
using iterator_category = /* see description */;
using iterator_concept = typename /*inner-iterator*/<Const>::iterator_concept;
using value_type =
remove_cvref_t<invoke_result_t</*maybe-const*/<Const, F>&,
/*REPEAT*/(range_reference_t<Base>, N)...>>;
using difference_type = range_difference_t<Base>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to</*inner-iterator*/<false>,
/*inner-iterator*/<Const>>;
constexpr decltype(auto) operator*() const noexcept(/* see description */);
constexpr iterator& operator++();
constexpr iterator operator++(int);
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x) requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x) requires random_access_range<Base>;
constexpr decltype(auto) operator[](difference_type n) const
requires random_access_range<Base>;
friend constexpr bool operator==(const iterator& x, const iterator& y);
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> && three_way_comparable<
/*inner-iterator*/<Const>>;
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for</*inner-iterator*/<Const>, /*inner-iterator*/<Const>>;
};
}
Class template std::ranges::adjacent_transform_view::sentinel
namespace std::ranges {
template<forward_range V, copy_constructible F, size_t N>
requires view<V> && (N > 0) && is_object_v<F> &&
regular_invocable<F&, /*REPEAT*/(range_reference_t<V>, N)...> &&
/*can-reference*/<invoke_result_t<F&,
/*REPEAT*/(range_reference_t<V>, N)...>>
template<bool Const>
class adjacent_transform_view<V, F, N>::sentinel {
/*inner-sentinel*/<Const> inner_; // exposition only
constexpr explicit sentinel(/*inner-sentinel*/<Const> inner); // exposition only
public:
sentinel() = default;
constexpr sentinel(sentinel<!Const> i)
requires Const && convertible_to</*inner-sentinel*/<false>,
/*inner-sentinel*/<Const>>;
template<bool OtherConst>
requires sentinel_for</*inner-sentinel*/<Const>, /*inner-iterator*/<OtherConst>>
friend constexpr bool operator==(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for</*inner-sentinel*/<Const>,
/*inner-iterator*/<OtherConst>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, InnerView>>
operator-(const iterator<OtherConst>& x, const sentinel& y);
template<bool OtherConst>
requires sized_sentinel_for</*inner-sentinel*/<Const>,
/*inner-iterator*/<OtherConst>>
friend constexpr range_difference_t</*maybe-const*/<OtherConst, InnerView>>
operator-(const sentinel& x, const iterator<OtherConst>& y);
};
}
Class template std::ranges::chunk_view for input ranges
namespace std::ranges {
template<class I>
constexpr I /*div-ceil*/(I num, I denom) { // exposition only
I r = num / denom;
if (num % denom)
++r;
return r;
}
template<view V>
requires input_range<V>
class chunk_view : public view_interface<chunk_view<V>> {
V base_ = V(); // exposition only
range_difference_t<V> n_ = 0; // exposition only
range_difference_t<V> remainder_ = 0; // exposition only
/*non-propagating-cache*/<iterator_t<V>> current_; // exposition only
// class chunk_view::/*outer-iterator*/
class /*outer-iterator*/; // exposition only
// class chunk_view::/*inner-iterator*/
class /*inner-iterator*/; // exposition only
public:
chunk_view() requires default_initializable<V> = default;
constexpr explicit chunk_view(V base, range_difference_t<V> n);
constexpr V base() const & requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr /*outer-iterator*/ begin();
constexpr default_sentinel_t end() noexcept;
constexpr auto size() requires sized_range<V>;
constexpr auto size() const requires sized_range<const V>;
};
template<class R>
chunk_view(R&& r, range_difference_t<R>) -> chunk_view<views::all_t<R>>;
}
Class std::ranges::chunk_view::outer_iterator for input ranges
namespace std::ranges {
template<view V>
requires input_range<V>
class chunk_view<V>::/*outer-iterator*/ {
chunk_view* parent_; // exposition only
constexpr explicit /*outer-iterator*/(chunk_view& parent); // exposition only
public:
using iterator_concept = input_iterator_tag;
using difference_type = range_difference_t<V>;
// class chunk_view::/*outer-iterator*/::value_type
struct value_type;
/*outer-iterator*/(/*outer-iterator*/&&) = default;
/*outer-iterator*/r& operator=(/*outer-iterator*/&&) = default;
constexpr value_type operator*() const;
constexpr /*outer-iterator*/& operator++();
constexpr void operator++(int);
friend constexpr bool operator==(const /*outer-iterator*/& x, default_sentinel_t);
friend constexpr difference_type operator-(default_sentinel_t y,
const /*outer-iterator*/& x)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
friend constexpr difference_type operator-(const /*outer-iterator*/& x,
default_sentinel_t y)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
};
}
Class std::ranges::chunk_view::outer_iterator::value_type for input ranges
namespace std::ranges {
template<view V>
requires input_range<V>
struct chunk_view<V>::/*outer-iterator*/::value_type
: view_interface<value_type> {
private:
chunk_view* parent_; // exposition only
constexpr explicit value_type(chunk_view& parent); // exposition only
public:
constexpr /*inner-iterator*/ begin() const noexcept;
constexpr default_sentinel_t end() const noexcept;
constexpr auto size() const
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
};
}
Class std::ranges::chunk_view::inner_iterator for input ranges
namespace std::ranges {
template<view V>
requires input_range<V>
class chunk_view<V>::/*inner-iterator*/ {
chunk_view* parent_; // exposition only
constexpr explicit /*inner-iterator*/(chunk_view& parent) noexcept; // exposition only
public:
using iterator_concept = input_iterator_tag;
using difference_type = range_difference_t<V>;
using value_type = range_value_t<V>;
/*inner-iterator*/(/*inner-iterator*/&&) = default;
/*inner-iterator*/& operator=(/*inner-iterator*/&&) = default;
constexpr const iterator_t<V>& base() const &;
constexpr range_reference_t<V> operator*() const;
constexpr /*inner-iterator*/& operator++();
constexpr void operator++(int);
friend constexpr bool operator==(const /*inner-iterator*/& x, default_sentinel_t);
friend constexpr difference_type operator-(default_sentinel_t y,
const /*inner-iterator*/& x)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
friend constexpr difference_type operator-(const /*inner-iterator*/& x,
default_sentinel_t y)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
};
}
Class template std::ranges::chunk_view for forward ranges
namespace std::ranges {
template<view V>
requires forward_range<V>
class chunk_view<V> : public view_interface<chunk_view<V>> {
V base_ = V(); // exposition only
range_difference_t<V> n_ = 0; // exposition only
// class template chunk_view::iterator
template<bool> class iterator; // exposition only
public:
chunk_view() requires default_initializable<V> = default;
constexpr explicit chunk_view(V base, range_difference_t<V> n);
constexpr V base() const & requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr auto begin() requires (!/*simple-view*/<V>) {
return iterator<false>(this, ranges::begin(base_));
}
constexpr auto begin() const requires forward_range<const V> {
return iterator<true>(this, ranges::begin(base_));
}
constexpr auto end() requires (!/*simple-view*/<V>) {
if constexpr (common_range<V> && sized_range<V>) {
auto missing = (n_ - ranges::distance(base_) % n_) % n_;
return iterator<false>(this, ranges::end(base_), missing);
} else if constexpr (common_range<V> && !bidirectional_range<V>) {
return iterator<false>(this, ranges::end(base_));
} else {
return default_sentinel;
}
}
constexpr auto end() const requires forward_range<const V> {
if constexpr (common_range<const V> && sized_range<const V>) {
auto missing = (n_ - ranges::distance(base_) % n_) % n_;
return iterator<true>(this, ranges::end(base_), missing);
} else if constexpr (common_range<const V> && !bidirectional_range<const V>) {
return iterator<true>(this, ranges::end(base_));
} else {
return default_sentinel;
}
}
constexpr auto size() requires sized_range<V>;
constexpr auto size() const requires sized_range<const V>;
};
}
Class template std::ranges::chunk_view::iterator for forward ranges
namespace std::ranges {
template<view V>
requires forward_range<V>
template<bool Const>
class chunk_view<V>::iterator {
using Parent = /*maybe-const*/<Const, chunk_view>; // exposition only
using Base = /*maybe-const*/<Const, V>; // exposition only
iterator_t<Base> current_ = iterator_t<Base>(); // exposition only
sentinel_t<Base> end_ = sentinel_t<Base>(); // exposition only
range_difference_t<Base> n_ = 0; // exposition only
range_difference_t<Base> missing_ = 0; // exposition only
constexpr iterator(Parent* parent, iterator_t<Base> current, // exposition only
range_difference_t<Base> missing = 0);
public:
using iterator_category = input_iterator_tag;
using iterator_concept = /* see description */;
using value_type = decltype(views::take(subrange(current_, end_), n_));
using difference_type = range_difference_t<Base>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>
&& convertible_to<sentinel_t<V>, sentinel_t<Base>>;
constexpr iterator_t<Base> base() const;
constexpr value_type operator*() const;
constexpr iterator& operator++();
constexpr iterator operator++(int);
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x)
requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x)
requires random_access_range<Base>;
constexpr value_type operator[](difference_type n) const
requires random_access_range<Base>;
friend constexpr bool operator==(const iterator& x, const iterator& y);
friend constexpr bool operator==(const iterator& x, default_sentinel_t);
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> &&
three_way_comparable<iterator_t<Base>>;
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>;
friend constexpr difference_type operator-(default_sentinel_t y, const iterator& x)
requires sized_sentinel_for<sentinel_t<Base>, iterator_t<Base>>;
friend constexpr difference_type operator-(const iterator& x, default_sentinel_t y)
requires sized_sentinel_for<sentinel_t<Base>, iterator_t<Base>>;
};
}
Class template std::ranges::slide_view
namespace std::ranges {
template<class V>
concept /*slide-caches-nothing*/ = random_access_range<V> // exposition only
&& sized_range<V>;
template<class V>
concept /*slide-caches-last*/ = // exposition only
!/*slide-caches-nothing*/<V> && bidirectional_range<V> && common_range<V>;
template<class V>
concept /*slide-caches-first*/ = // exposition only
!/*slide-caches-nothing*/<V> && !/*slide-caches-last*/<V>;
template<forward_range V>
requires view<V>
class slide_view : public view_interface<slide_view<V>> {
V base_ = V(); // exposition only
range_difference_t<V> n_ = 0; // exposition only
// class template slide_view::iterator
template<bool> class iterator; // exposition only
// class slide_view::sentinel
class sentinel; // exposition only
public:
slide_view() requires default_initializable<V> = default;
constexpr explicit slide_view(V base, range_difference_t<V> n);
constexpr auto begin()
requires (!(/*simple-view*/<V> && /*slide-caches-nothing*/<const V>));
constexpr auto begin() const requires /*slide-caches-nothing*/<const V>;
constexpr auto end()
requires (!(/*simple-view*/<V> && /*slide-caches-nothing*/<const V>));
constexpr auto end() const requires /*slide-caches-nothing*/<const V>;
constexpr auto size() requires sized_range<V>;
constexpr auto size() const requires sized_range<const V>;
};
template<class R>
slide_view(R&& r, range_difference_t<R>) -> slide_view<views::all_t<R>>;
}
Class template std::ranges::slide_view::iterator
namespace std::ranges {
template<forward_range V>
requires view<V>
template<bool Const>
class slide_view<V>::iterator {
using Base = /*maybe-const*/<Const, V>; // exposition only
iterator_t<Base> current_ = iterator_t<Base>(); // exposition only
iterator_t<Base> last_ele_ = iterator_t<Base>(); // exposition only,
// present only if Base models slide-caches-first
range_difference_t<Base> n_ = 0; // exposition only
constexpr iterator(iterator_t<Base> current, range_difference_t<Base> n) // exposition only
requires (!/*slide-caches-first*/<Base>);
constexpr iterator(iterator_t<Base> current, iterator_t<Base> last_ele, // exposition only
range_difference_t<Base> n)
requires /*slide-caches-first*/<Base>;
public:
using iterator_category = input_iterator_tag;
using iterator_concept = /* see description */;
using value_type = decltype(views::counted(current_, n_));
using difference_type = range_difference_t<Base>;
iterator() = default;
constexpr iterator(iterator<!Const> i)
requires Const && convertible_to<iterator_t<V>, iterator_t<Base>>;
constexpr auto operator*() const;
constexpr iterator& operator++();
constexpr iterator operator++(int);
constexpr iterator& operator--() requires bidirectional_range<Base>;
constexpr iterator operator--(int) requires bidirectional_range<Base>;
constexpr iterator& operator+=(difference_type x)
requires random_access_range<Base>;
constexpr iterator& operator-=(difference_type x)
requires random_access_range<Base>;
constexpr auto operator[](difference_type n) const
requires rrandom_access_range<Base>;
friend constexpr bool operator==(const iterator& x, const iterator& y);
friend constexpr bool operator<(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator<=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr bool operator>=(const iterator& x, const iterator& y)
requires random_access_range<Base>;
friend constexpr auto operator<=>(const iterator& x, const iterator& y)
requires random_access_range<Base> &&
three_way_comparable<iterator_t<Base>>;
friend constexpr iterator operator+(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr iterator operator+(difference_type n, const iterator& i)
requires random_access_range<Base>;
friend constexpr iterator operator-(const iterator& i, difference_type n)
requires random_access_range<Base>;
friend constexpr difference_type operator-(const iterator& x, const iterator& y)
requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>;
};
}
Class std::ranges::slide_view::sentinel
namespace std::ranges {
template<forward_range V>
requires view<V>
class slide_view<V>::sentinel {
sentinel_t<V> end_ = sentinel_t<V>(); // exposition only
constexpr explicit sentinel(sentinel_t<V> end); // exposition only
public:
sentinel() = default;
friend constexpr bool operator==(const iterator<false>& x, const sentinel& y);
friend constexpr range_difference_t<V>
operator-(const iterator<false>& x, const sentinel& y)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
friend constexpr range_difference_t<V>
operator-(const sentinel& y, const iterator<false>& x)
requires sized_sentinel_for<sentinel_t<V>, iterator_t<V>>;
};
}
Class template std::ranges::chunk_by_view
namespace std::ranges {
template<forward_range V, indirect_binary_predicate<iterator_t<V>, iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class chunk_by_view : public view_interface<chunk_by_view<V, Pred>> {
V base_ = V(); // exposition only
/*copyable-box*/<Pred> pred_ = Pred(); // exposition only
// class chunk_by_view::iterator
class iterator; // exposition only
public:
chunk_by_view()
requires default_initializable<V> && default_initializable<Pred> = default;
constexpr explicit chunk_by_view(V base, Pred pred);
constexpr V base() const & requires copy_constructible<V> { return base_; }
constexpr V base() && { return std::move(base_); }
constexpr const Pred& pred() const;
constexpr iterator begin();
constexpr auto end();
constexpr iterator_t<V> /*find-next*/(iterator_t<V>); // exposition only
constexpr iterator_t<V> /*find-prev*/(iterator_t<V>) // exposition only
requires bidirectional_range<V>;
};
template<class R, class Pred>
chunk_by_view(R&&, Pred) -> chunk_by_view<views::all_t<R>, Pred>;
}
Class template std::ranges::chunk_by_view::iterator
namespace std::ranges {
template<forward_range V, indirect_binary_predicate<iterator_t<V>, iterator_t<V>> Pred>
requires view<V> && is_object_v<Pred>
class chunk_by_view<V, Pred>::iterator {
chunk_by_view* parent_ = nullptr; // exposition only
iterator_t<V> current_ = iterator_t<V>(); // exposition only
iterator_t<V> next_ = iterator_t<V>(); // exposition only
constexpr iterator(chunk_by_view& parent, iterator_t<V> current, // exposition only
iterator_t<V> next);
public:
using value_type = subrange<iterator_t<V>>;
using difference_type = range_difference_t<V>;
using iterator_category = input_iterator_tag;
using iterator_concept = /* see description */;
iterator() = default;
constexpr value_type operator*() const;
constexpr iterator& operator++();
constexpr iterator operator++(int);
constexpr iterator& operator--() requires bidirectional_range<V>;
constexpr iterator operator--(int) requires bidirectional_range<V>;
friend constexpr bool operator==(const iterator& x, const iterator& y);
friend constexpr bool operator==(const iterator& x, default_sentinel_t);
};
}
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