std::incrementable - cppreference.com

From cppreference.com

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