std::ranges::views::split, std::ranges::split_view

 

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

 

std::ranges::split_view

Member functions

split_view::split_view (C++20)

split_view::base (C++20)

split_view::begin (C++20)

split_view::end (C++20)

Nested classes

split_view::iterator (C++20)

split_view::sentinel (C++20)

Deduction guides

 

Defined in header <ranges>
template< ranges::forward_range V, ranges::forward_range Pattern > requires ranges::view<V> && ranges::view<Pattern> &&   std::indirectly_comparable<ranges::iterator_t<V>, ranges::iterator_t<Pattern>,                              ranges::equal_to> class split_view : public ranges::view_interface<split_view<V, Pattern>>	(1)	(since C++20)
namespace views {     inline constexpr /*unspecified*/ split = /*unspecified*/; }	(2)	(since C++20)
Call signature
template< ranges::viewable_range R, class Pattern >     requires /* see below */ constexpr ranges::view auto split( R&& r, Pattern&& pattern );
template< class Pattern > constexpr /*range adaptor closure*/ split( Pattern&& pattern );

1) split_view takes a view and a delimiter, and splits the view into subranges on the delimiter.

2) Ranges adaptor object. The expression views::split(e, p) is expression-equivalent to split_view(e, p) for any suitable subexpressions e and p.

split_view models the concepts forward_range, and common_range when the underlying view V models respective concepts.

The inner range (ranges::range_reference_t<split_view>) is a ranges::subrange<ranges::iterator_t<V>>, which models common_range, models sized_range when ranges::iterator_t<V> models std::sized_sentinel_for<ranges::iterator_t<V>>, and models contiguous_range, random_access_range, bidirectional_range, and forward_range when V models respective concepts.

Expression-equivalent

Expression e is expression-equivalent to expression f, if e and f have the same effects, either are both potentially-throwing or are both not potentially-throwing (i.e. noexcept(e) == noexcept(f)), and either are both constant subexpressions or are both not constant subexpressions.

Data members

Typical implementations of split_view hold three non-static data members:

• the underlying view of type V (shown here as base_ for exposition only), and
• the pattern (shown here as pattern_ for exposition only) that is used as a delimiter to split the underlying view.
• an object equivalent to std::optional<ranges::subrange<ranges::iterator_t<V>>> (shown here as cached_begin_ for exposition only) that caches the result of a first call to begin().

Member functions

(constructor) (C++20)	constructs a split_view (public member function)
base (C++20)	returns a copy of the underlying (adapted) view (public member function)
begin (C++20)	returns an iterator to the beginning (public member function)
end (C++20)	returns an iterator or a sentinel to the end (public member function)
find_next (C++20)	searches for the next occurrence of the pattern (exposition-only member function)
Inherited from std::ranges::view_interface
empty (C++20)	Returns whether the derived view is empty. Provided if it satisfies forward_range. (public member function of std::ranges::view_interface<D>)
operator bool (C++20)	Returns whether the derived view is not empty. Provided if ranges::empty is applicable to it. (public member function of std::ranges::view_interface<D>)
front (C++20)	Returns the first element in the derived view. Provided if it satisfies forward_range. (public member function of std::ranges::view_interface<D>)

Nested classes

iterator (C++20)	the iterator type (exposition-only member class)
sentinel (C++20)	the sentinel type (exposition-only member class)

Example

A link to check the example: wandbox

Run this code

#include <iostream>
#include <iomanip>
#include <ranges>
#include <string_view>
 
int main() {
    constexpr std::string_view words{"Hello-_-C++-_-20-_-!"};
    constexpr std::string_view delim{"-_-"};
    for (const auto word : std::views::split(words, delim)) {
        std::cout << std::quoted(std::string_view(word.begin(), word.end())) << ' ';
    }
}

Output:

"Hello" "C++" "20" "!"

See also

ranges::lazy_split_viewviews::lazy_split (C++20)	a view over the subranges obtained from splitting another view using a delimiter (class template) (range adaptor object)
ranges::join_viewviews::join (C++20)	a view consisting of the sequence obtained from flattening a view of ranges (class template) (range adaptor object)