std::ranges::crbegin - cppreference.com (original) (raw)

| Defined in header | | | | ------------------------------------------------------------------------------------------------------------- | | ------------------------------------------ | | Defined in header | | | | inline namespace /* unspecified */ { inline constexpr /* unspecified */ crbegin = /* unspecified */; } | | (since C++20) (customization point object) | | Call signature | | | | template< class T > requires /* see below */ constexpr /* see below */ auto crbegin( T&& t ); | | (since C++20) |

The return type models std::input_or_output_iterator and constant-iterator(since C++23) in all cases.

Customization point objects

The name ranges::crbegin denotes a customization point object, which is a const function object of a literal semiregular class type. See CustomizationPointObject for details.

[edit] Example

#include #include #include #include   int main() { std::vector v{3, 1, 4}; auto vi = std::ranges::crbegin(v); assert(*vi == 4); ++vi; // OK, iterator object is mutable assert(*vi == 1); // *vi = 13; // Error: underlying element is read-only   int a[]{-5, 10, 15}; auto ai = std::ranges::crbegin(a); assert(*ai == 15);   // auto x_x = std::ranges::crbegin(std::vector{6, 6, 6}); // ill-formed: the argument is an rvalue (see Notes ↑)   auto si = std::ranges::crbegin(std::span{a}); // OK assert(*si == 15); static_assert ( std::ranges::enable_borrowed_range<std::remove_cv_t<decltype(std::span{a})>> ); }

[edit] See also

| | returns a reverse iterator to a range(customization point object)[edit] | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | returns a reverse iterator to the beginning of a container or array (function template) [edit] |