3711. Missing preconditions for slide_view constructor

Section: 25.7.30.2 [range.slide.view] Status: C++23 Submitter: Hewill Kang Opened: 2022-06-10 Last modified: 2023-11-22

Priority: Not Prioritized

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Discussion:

It doesn't make sense for slide_view when n is not positive, we should therefore add a precondition for its constructor just like we did for chunk_view.

Daniel:

Indeed the accepted paper describes the intention in P2442R1 Section 4.2 by saying that "It is a precondition that N is positive" in the design wording but omitted to add a normative precondition in the proposed wording.

[2022-06-21; Reflector poll]

Set status to Tentatively Ready after six votes in favour during reflector poll.

[2022-07-15; LWG telecon: move to Ready]

[2022-07-25 Approved at July 2022 virtual plenary. Status changed: Ready → WP.]

Proposed resolution:

This wording is relative to N4910.

1. Modify 25.7.30.2 [range.slide.view] as indicated:

   constexpr explicit slide_view(V base, range_difference_t<V> n);
   

   -?- Preconditions: n > 0 is true.

   -1- Effects: Initializes base_ with std::move(base) and n_ with n.