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Section: 21.3.8.7 [meta.trans.other] Status: C++20 Submitter: Casey Carter Opened: 2018-07-07 Last modified: 2021-02-25
Priority: 0
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Discussion:
21.3.8.7 [meta.trans.other]/3.2 states:
[Let] XREF(A) denote a unary class template T such that T<U> denotes the same type as U with the addition of A’s cv and reference qualifiers, for a non-reference cv-unqualified type U,which is nonsensical: a specialization of a class template cannot possibly be a cv-qualified type or reference type. XREF(A) must be a unary alias template.
[2018-09-11; Status set to Tentatively Ready after five positive votes on the reflector]
[2018-11, Adopted in San Diego]
Proposed resolution:
This wording is relative to N4762.
Change 21.3.8.7 [meta.trans.other] as indicated:
-3- Let:
(3.1) — CREF(A) be add_lvalue_reference_t<const remove_reference_t<A>>,
(3.2) — XREF(A) denote a unary
classalias template T such that T<U> denotes the same type as U with the addition of A’s cv and reference qualifiers, for a non-reference cv-unqualified type U,(3.3) — COPYCV(FROM, TO) be an alias for type TO with the addition of FROM’s top-level cv-qualifiers. [Example: COPYCV(const int, volatile short) is an alias for const volatile short. —end example]