constexpr /* see below */ size() const
    requires (K == ranges::subrange_kind::sized);
(since C++20)

Obtains the number of elements in the subrange.

The return type is the corresponding unsigned version of std::iter_difference_t<I>.



Return value

s_ - i_ explicitly converted to the return type, where i_ and s_ are the stored iterator and sentinel respectively, if the size is not stored.

Otherwise, the stored size.


The size is stored into a subrange if and only if K == ranges::subrange_kind::sized but std::sized_sentinel_for<S, I> is not satisfied.


See also

checks whether the subrange is empty
(public member function)
returns the size of a container or array
(function template)
returns an integer equal to the size of a range
(customization point object)

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