P2642: LWG 2024/02/28 review

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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The issue names P2642 and the sections [mdspan.layout.rightpadded.obs] and [mdspan.submdspan.mapping], but no file or test. Start by locating the P2642 wording in the repository and review the listed constructor, observer, and submdspan mapping paragraphs. Done means applying the specified editorial corrections, adding the drafting Note, and adding the requested Editorial Wiki entry.