std::incrementable

 

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Defined in header <iterator>
template< class I > concept incrementable = std::regular<I> && std::weakly_incrementable<I> && requires(I i) { { i++ } -> std::same_as<I>; };		(since C++20)

This concept specifies requirements on types that can be incremented with the pre- and post-increment operators, whose increment operations are equality-preserving, and the type is std::equality_comparable.

Unlike with std::weakly_incrementable, which only support single-pass algorithms, multi-pass one-directional algorithms can be used with types that model std::incrementable.

Semantic requirements

I models std::incrementable only if given any two incrementable objects a and b of type I:

• bool(a == b) implies bool(a++ == b), and
• bool(a == b) implies bool(((void)a++, a) == ++b).

Equality preservation

Expressions declared in requires expressions of the standard library concepts are required to be equality-preserving (except where stated otherwise).

See also

weakly_incrementable (C++20)	specifies that a semiregular type can be incremented with pre- and post-increment operators (concept)
same_as (C++20)	specifies that a type is the same as another type (concept)