r/wg21
P3856R5 - New reflection metafunction - is_structural_type WG21Update
Posted by u/reflection_paper_feed · 3 hr. ago

Document: P3856R5
Authors: Jagrut Dave, Alisdair Meredith
Date: 2026-02-10
Audience: LEWG/LWG
Prior revision: P3856R4 thread

Minor revision - improved wording based on Barry Revzin's feedback. The trait name was also updated from is_structural_type_v to is_structural_v for consistency with other type traits (e.g. is_const_v, not is_const_type_v). Same proposal, cleaner spec text.

▲ 18 points (94% upvoted) · 5 comments
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u/nttp_power_user 12 points 2 hr. ago

The trait rename from is_structural_type_v to is_structural_v is correct. We have is_const_v not is_const_type_v. Consistency matters in the type traits header. Good catch from Barry.

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u/revision_churn_tracker 8 points 2 hr. ago

R4 to R5 in two weeks. Wording feedback turnaround. This is the process working as intended.

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u/barry_review_quality 6 points 1 hr. ago

Barry's wording reviews are reliably thorough. If this passed his review, the spec text is probably solid.

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u/poc_implementation_reader 4 points 47 minutes ago

No changes to the proof-of-concept implementation in this revision. The R4 Godbolt link still works. The changes are purely wording.

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