Namespaces
Variants
Views
Actions

std::ranges::subrange<I,S,K>::prev

From cppreference.com
< cpp‎ | ranges‎ | subrange
 
 
 
std::ranges::subrange
Member functions
Observers
Iterator operations
subrange::prev
(C++20)
Deduction guides
Non-member functions
(C++20)
Helper types
(C++20)
 
[[nodiscard]] constexpr subrange prev( std::iter_difference_t<I> n = 1 ) const
    requires std::bidirectional_iterator<I>;
(since C++20)

Obtains a subrange whose iterator is decremented by n times or incremented by min(-n, size()) times respect to that of *this, when n >= 0 or n < 0 respectively.

Equivalent to auto tmp = *this; tmp.advance(-n); return tmp;. The behavior is undefined if the iterator is decremented after being a non-decrementable value.

Contents

[edit] Parameters

n - number of minimal decrements of the iterator

[edit] Return value

A subrange whose iterator is decremented by n times or incremented by min(-n, size()) times respect to that of *this, when n >= 0 or n < 0 respectively.

[edit] Complexity

Generally n decrements or min(-n, size()) increments on the iterator, when n >= 0 or n < 0 respectively.

Constant if I models random_access_iterator, and either n >= 0 or std::sized_sentinel_for<S, I> is modeled.

[edit] Example

[edit] See also

(C++20)
advances the iterator by given distance and returns the original subrange
(public member function) [edit]
(C++20)
advances the iterator by given distance
(public member function) [edit]
(C++11)
decrement an iterator
(function template) [edit]
decrement an iterator by a given distance or to a bound
(niebloid) [edit]