std::default_sentinel_t, std::default_sentinel - cppreference.com (original) (raw)

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Defined in header
struct default_sentinel_t {};	(1)	(since C++20)
inline constexpr default_sentinel_t default_sentinel{};	(2)	(since C++20)

default_sentinel_t is an empty class type used to denote the end of a range. It can be used together with iterator types that know the bound of their range (e.g., std::counted_iterator).
default_sentinel is a constant of type default_sentinel_t.

[edit] Example

Run this code

#include #include #include int main() { const std::string s = "Quick brown fox."; const std::regex words_regex("[^\s]+"); const std::ranges::subrange words( std::sregex_iterator(s.begin(), s.end(), words_regex), std::default_sentinel); std::println("Found {} words:", std::ranges::distance(words)); for (const std::smatch& match : words) std::println("{}", match.str()); }

Output:

Found 3 words: Quick brown fox.

[edit] See also

istream_iterator	input iterator that reads from std::basic_istream (class template) [edit]
istreambuf_iterator	input iterator that reads from std::basic_streambuf (class template) [edit]
counted_iterator(C++20)	iterator adaptor that tracks the distance to the end of the range (class template) [edit]