Scroll to navigation

std::experimental::ranges::prev(3) C++ Standard Libary std::experimental::ranges::prev(3)


std::experimental::ranges::prev - std::experimental::ranges::prev


Defined in header <experimental/ranges/iterator>
namespace {
(ranges TS)
constexpr /* unspecified */ prev = /* unspecified */; (customization point
Call signature
template< Iterator I > (1)
constexpr I prev(I i);
template< Iterator I > (2)
constexpr I prev(I i, ranges::difference_type_t<I> n);
template< Iterator I >
constexpr I prev(I i, ranges::difference_type_t<I> n, I (3)

Decrements the iterator i n times, or until bound is reached, whichever comes first,
and returns the decremented iterator.

1) Equivalent to --i; return i;.
2) Equivalent to ranges::advance(i, -n); return i;.
3) Equivalent to ranges::advance(i, -n, bound); return i;.

Customization point objects

The name ranges::prev denotes a customization point object, which is a function
object of a literal Semiregular class type (denoted, for exposition purposes, as
PrevT). All instances of PrevT are equal. Thus, ranges::prev can be copied freely
and its copies can be used interchangeably.

Given a set of types Args..., if std::declval<Args>()... meet the requirements for
arguments to ranges::prev above, PrevT will satisfy ranges::Invocable<const PrevT,
Args...>. Otherwise, no function call operator of PrevT participates in overload

In every translation unit in which ranges::prev is defined, it refers to the same
instance of the customization point object. (This means that it can be used freely
in things like inline functions and function templates without violating the
one-definition rule.)

Return value

The decremented iterator.


This section is incomplete
Reason: no example

See also

prev decrement an iterator
(C++11) (function template)
advance advances an iterator by given distance
(function template)
next increment an iterator
(function template)
returns the distance between an iterator and a sentinel, or between the
distance beginning and the end of a range
(function template)