std::ranges::range

 

C++

Compiler support

Freestanding and hosted

Language

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical specifications

Symbols index

External libraries

 

Ranges library

Range access
begin cbegin end cend	rbegin crbegin rend crend	size ssize data cdata	empty
Range primitives
iterator_tsentinel_t	range_size_trange_difference_t	range_reference_trange_rvalue_reference_t	range_value_t
Dangling iterator handling
dangling	borrowed_iterator_t	borrowed_subrange_t
Range concepts
range borrowed_range    sized_range	common_range view viewable_range	input_range output_range forward_range	bidirectional_range random_access_range contiguous_range
Views
view_interface	subrange
Factories
empty_viewviews::empty	single_viewviews::single	iota_viewviews::iota	basic_istream_viewviews::istream
Adaptors
views::all_tviews::all ref_view owning_view common_viewviews::common reverse_viewviews::reverse views::counted zip_viewviews::zip (C++23)(C++23)	take_viewviews::take take_while_viewviews::take_while drop_viewviews::drop drop_while_viewviews::drop_while zip_transform_viewviews::zip_transform (C++23)(C++23)	elements_viewviews::elements keys_viewviews::keys values_viewviews::values transform_viewviews::transform adjacent_viewviews::adjacent (C++23)(C++23)	filter_viewviews::filter join_viewviews::join split_viewviews::split lazy_split_viewviews::lazy_split adjacent_transform_viewviews::adjacent_transform (C++23)(C++23)
Range adaptor objects
Range adaptor closure objects
Helper items
copyable-box	simple-view

 

Defined in header <ranges>
template< class T > concept range = requires(T& t) {   ranges::begin(t); // equality-preserving for forward iterators   ranges::end  (t); };

The range concept defines the requirements of a type that allows iteration over its elements by providing an iterator and sentinel that denote the elements of the range.

Semantic requirements

Given an expression E such that decltype((E)) is T, T models range only if

• [ranges::begin(E), ranges::end(E)) denotes a range, and
• both ranges::begin(E) and ranges::end(E) are amortized constant time and do not alter the value of E in a manner observable to equality-preserving expressions, and
• if the type of ranges::begin(E) models forward_iterator, ranges::begin(E) is equality-preserving (in other words, forward iterators support multi-pass algorithms)

Note: In the definition above, the required expressions ranges::begin(std::forward<T>(t)) and ranges::end(std::forward<T>(t)) do not require implicit expression variations.