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[2607:f8b0:4001:c0b::229]) by mx.google.com with ESMTPS id r133si22523811ith.58.2016.08.23.06.32.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 23 Aug 2016 06:32:04 -0700 (PDT) Received-SPF: pass (google.com: domain of schaub.johannes@googlemail.com designates 2607:f8b0:4001:c0b::229 as permitted sender) client-ip=2607:f8b0:4001:c0b::229; Original-Received: by mail-it0-x229.google.com with SMTP id x131so146887473ite.0 for ; Tue, 23 Aug 2016 06:32:04 -0700 (PDT) X-Received: by 10.36.112.11 with SMTP id f11mr27920132itc.57.1471959123964; Tue, 23 Aug 2016 06:32:03 -0700 (PDT) Original-Received: by 10.107.16.38 with HTTP; Tue, 23 Aug 2016 06:32:03 -0700 (PDT) In-Reply-To: <5aceab3e-d3e6-42b0-a735-846405f33633@isocpp.org> X-Original-Sender: schaub.johannes@googlemail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@googlemail.com; spf=pass (google.com: domain of schaub.johannes@googlemail.com designates 2607:f8b0:4001:c0b::229 as permitted sender) smtp.mailfrom=schaub.johannes@googlemail.com; dmarc=pass (p=QUARANTINE dis=NONE) header.from=googlemail.com X-Original-From: Johannes Schaub Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:27899 Archived-At: 2016-08-23 15:29 GMT+02:00 TONGARI J : > On Tuesday, August 23, 2016 at 5:46:36 PM UTC+8, TONGARI J wrote: >> >> On Tuesday, August 23, 2016 at 3:00:29 PM UTC+8, Johannes Schaub wrote: >>> >>> Unfortunately, "nondeduced" does not work here, because the pack >>> expansion is outside of it. Compilers appear to expand the pack before >>> deducing the elements: >>> >>> >>> template >>> void f(void(nodeduced_t..., Z)) { } >>> >>> void g(int, char) { } >>> >>> int main() { >>> f(g); >>> } >>> >>> This will not compile, apparently compilers create "void(int, >>> nondeduced_t, Z)" and try to compare "nondeduced_t" against >>> "char". My "protected" prevents this "growing" of the parameter pack. >> >> >> What are you trying to do with this example? > > > Ah, so you want to deduce `Z` but have `T...` explicitly specified in that > example, right? > It's strange that the following works but the above example doesn't...`Z` > somehow becomes non-deducible. > template > void f(void(nodeduced_t..., char)) { } > This works because you never try to call "f" with anything. -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. 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