This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 114a. See for the official list.


1896. Repeated alias templates

Section: 13.7.8  [temp.alias]     Status: CD6     Submitter: Mike Miller     Date: 2014-03-18

[Accepted at the November, 2020 meeting as part of paper P1787R6 and moved to DR at the February, 2021 meeting.]

The current wording of the Standard does not permit repeated alias template declarations within a scope, but some current implementations allow it, presumably by analogy with typedef declarations. Should the Standard be changed to permit this usage?

Notes from the November, 2014 meeting:

CWG agreed that the usage should be permitted, provided that the dependent types are equivalent. Note that this is a weaker requirement than the token-for-token identity of the ODR, since alias templates are not definitions per Clause 13 [temp] paragraph 1.