P2642: LWG 2024/02/28 review

[mhoemmen]

P2642: LWG 2024/02/28 review

Changes from previous review

"Paragraph numbers are off at the top of the wording." (This is still the case; it awaits more time for formatting.)

LWG is pleased on 2024/02/28. Also pleased with the updated green diff style.

Extra LEAST-MULTIPLE-AT-LEAST condition on constructors.

Paragraphs 6 and 9 of observers now use preferred if/else/otherwise format.

Resuming

Converting ctor from layout_stride::mapping to layout_right_padded::mapping.

11.1 needs a period; make it a complete sentence. Preconditions generally have implicit and between them, so each can be a complete sentence.

18.1 has a missing closing backtick for true. Also, make those Constraints each a stand-alone sentence, just like the preconditions. (Constraints for converting constructor from LayoutLeftPaddedMapping.)

20: Capital letter for direct-non-list-initializes.

21: Remove space between ! and rest of expression.

Note after 21: "... affects neither the constraints nor the preconditions."

[mdspan.layout.rightpadded.obs]

Wording for strides() could declare the function on one line instead of two.

Para 2 Returns: Reformat as one sentence, since it's just two bullets. (Just remove the bullets; leave the current structure.)

(Just for future reference: para 5 is by-construction correct because of the new Mandates and Preconditions.)

Para 9 under stride is a bit wacky, but OK to leave alone, since it's consistent with Ranges. (Add an entry to the Editorial Wiki about this.)

[mdspan.submdspan.mapping]

(Corresponding to 4.2, there was a bug in the current draft. They actually need to be ordered.)

Add a drafting Note to explain that 4.2 is a drive-by fix, an intentional deviation from the current Draft that LWG reviewed and approved.

layout_right specialization of submdspan_mapping, para 1.3, first inner bullet: Add a comma, as with layout_left above, to separate out the values.

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[mhoemmen]

@crtrott Could you please make a PR for the changes that you worked on during yesterday's review? It's OK if it's not done; I just want to make sure it's not lost. Thanks!