std::ranges::viewable_range

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

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Technical Specifications

 

Ranges library

Range access
begincbegin endcend	rbegincrbegin rendcrend	size empty datacdata
Range primitives
iteartor_tsentinel_t	range_difference_trange_value_t	range_reference_trange_rvalue_reference_t
Dangling iterator handling
dangling	safe_iterator_t	safe_subrange_t
Range concepts
range sized_range view	input_range output_range forward_range	bidirectional_range random_access_range contiguous_range	common_range viewable_range
Views
view_interface	subrange
Semiregular wrapper
Factories
empty_viewviews::empty	single_viewviews::single	iota_viewviews::iota	views::counted
Adaptors
all_viewviews::all join_viewviews::join take_viewviews::take basic_istream_viewistream_view	ref_view                                split_viewviews::split take_while_viewviews::take_while elements_viewviews::elements	common_viewviews::common transform_viewviews::transform drop_viewviews::drop keys_viewviews::keys	reverse_viewviews::reverse filter_viewviews::filter drop_while_viewviews::drop_while values_viewviews::values

 

Defined in header <ranges>
template<class T>   concept viewable_range =     ranges::range<T> && (__ForwardingRange<T> || ranges::view<std::decay_t<T>>);

The viewable_range concept is a refinement of range that describes a range that can be safely converted into a view.

(note __ForwardingRange is the exposition-only concept defined in range)