From cppreference.com
Defined in header
template<ranges::forward_rangeV,ranges::forward_rangePattern>requiresranges::view<V>&&ranges::view<Pattern>&&std::indirectly_comparable<ranges::iterator_t<V>,ranges::iterator_t<Pattern>,ranges::equal_to>classsplit_view:publicranges::view_interface<split_view<V,Pattern>> (1) (since C++20)namespaceviews{inlineconstexpr/* unspecified */split=/* unspecified */;} (2) (since C++20)Call signature
template<ranges::viewable_rangeR,classPattern>requires/* see below */constexprranges::viewautosplit(R&&r,Pattern&&pattern);(since C++20)template<classPattern>constexpr/* range adaptor closure */split(Pattern&&pattern);(since C++20)1)split_view takes a
and a delimiter, and splits the
into subranges on the delimiter.
split_view models the concepts
, and
when the underlying
V models respective concepts.
The inner range (ranges::range_reference_t<split_view>) is a ranges::subrange<ranges::iterator_t<V>>, which models
, models
when ranges::iterator_t<V> models std::sized_sentinel_for<ranges::iterator_t<V>>, and models
,
,
, and
when V models respective concepts.
Unlike
, split_view maintains the continuity of the subrange, making it suitable for string splitting.
Data members
Member Description Vbase_(private)the underlying (adapted)
(exposition-only member object*)Patternpattern_(private)the pattern object that is used as a delimiter to split the underlying
(exposition-only member object*)
<ranges::subrange
<ranges::iterator_t<V>>>cached_begin_(private)an object that caches the result of the first call to
(exposition-only member object*)Member functions
constructs a split_view
(public member function)
returns a copy of the underlying (adapted) view
(public member function)
returns an iterator to the beginning
(public member function)
returns an iterator or a sentinel to the end
(public member function)
searches for the next occurrence of the pattern
(exposition-only member function*) Inherited from
returns whether the derived view is empty, provided only if it satisfies
or
(public member function of std::ranges::view_interface<D>)
(C++23)
returns a constant iterator to the beginning of the range
(public member function of std::ranges::view_interface<D>)
(C++23)
returns a sentinel for the constant iterator of the range
(public member function of std::ranges::view_interface<D>)
returns whether the derived view is not empty, provided only if
is applicable to it
(public member function of std::ranges::view_interface<D>)
returns the first element in the derived view, provided if it satisfies
(public member function of std::ranges::view_interface<D>)
Nested classes
the iterator type
(exposition-only member class*)the sentinel type
(exposition-only member class*)
Notes
Before
, split_view used a lazy mechanism for splitting, and thus could not keep the bidirectional, random access, or contiguous properties of the underlying view, or make the iterator type of the inner range same as that of the underlying view. Consequently, it is redesigned by
, and the lazy mechanism is moved to
.
The delimiter pattern generally should not be an ordinary string literal, as it will consider the null terminator to be necessary part of the delimiter; therefore, it is advisable to use a
literal instead.
Example
Run this code
#include<iomanip>#include<iostream>#include<ranges>#include<string_view>intmain(){usingstd::operator""sv;constexprautowords{"Hello^_^C++^_^20^_^!"sv};constexprautodelim{"^_^"sv};for(constautoword:std::views::split(words,delim))// with string_view's C++23 range constructor:std::cout<<std::quoted(std::string_view(word))<<' ';std::cout<<'\n';}Output:
"Hello" "C++" "20" "!" Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior
C++20 the old split_view was too lazy to be easily used it is redesigned See also