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Section: 184.108.40.206 [span.cons] Status: C++20 Submitter: Lars Gullik Bjønnes Opened: 2019-04-03 Last modified: 2021-02-25
Priority: Not Prioritized
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It seems that this was left out of P1089. The constraint on span() (220.127.116.11 [span.cons]) in the current draft is:
Constraints: Extent <= 0 is true.
This does not seem to make much sense.The proposal is to change the constraint to be:
[2019-06-09; Priority to 0 and Status to Tentatively Ready after five positive votes on the reflector.]
Constraints: Extent == dynamic_extent || Extent == 0 is true.
This wording is relative to N4810.
Modify 18.104.22.168 [span.cons] as indicated:
constexpr span() noexcept;
-1- Constraints: Extent
<= 0 is true.