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[84.60.195.12]) by smtp.gmail.com with ESMTPSA id q6sm3857997edk.55.2017.10.15.09.27.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 15 Oct 2017 09:27:39 -0700 (PDT) In-Reply-To: <5accfbfb-91b3-489e-9e2d-b82149b5ce8e@isocpp.org> Content-Language: en-US X-Original-Sender: jonathanmueller.dev@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=b5YWcYf3; spf=pass (google.com: domain of jonathanmueller.dev@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=jonathanmueller.dev@gmail.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com 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:34947 Archived-At: On 15.10.2017 18:21, Nicol Bolas wrote: >=20 >=20 > On Sunday, October 15, 2017 at 11:48:56 AM UTC-4, Jonathan M=C3=BCller wr= ote: >=20 > On 15.10.2017 17:14, Nicol Bolas wrote: > > > > =C2=A0 =C2=A0 Although the "virtual overhead" is acceptible in man= y cases, > it is > > =C2=A0 =C2=A0 an evidence that "PMRs" still has room to improve. > > > > > > Replacing "virtual overhead" with "type-erased access overhead" > is not > > an improvement. > > >=20 > It would be an improvement if you could decide between a type erased > allocator and a template allocator. >=20 >=20 > I don't know what you mean by "template allocator". If you're talking=20 > about like `vector`, well, we already have that right now.= =20 > Users of containers can decide between a virtual allocator and a=20 > "template allocator". Why does "type-erased" need to be an option,=20 > specifically? >=20 Yes, I meant `vector` and yes, we have both options=20 already, so yes, I don't think OP's idea is necessary. However, for a hypothetical redesign of the standard library I think=20 this should be considered. An allocator interface similar to the simple PMRs as opposed to the=20 complexity mess that is Allocator, but instead of virtual functions and=20 class hierarchy it is "concept-based" like Allocator and provides the=20 possibility of using type erasure. --=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/4aa86771-6ade-02fa-b77e-6f0e33f230ac%40gmail.com= .. .