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[209.85.220.41]) by mx.google.com with SMTPS id e9sor5605905ljk.10.2019.03.12.11.33.00 for (Google Transport Security); Tue, 12 Mar 2019 11:33:00 -0700 (PDT) Received-SPF: pass (google.com: domain of daniel.kruegler@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a2e:5715:: with SMTP id l21mr4125881ljb.105.1552415579995; Tue, 12 Mar 2019 11:32:59 -0700 (PDT) In-Reply-To: X-Original-Sender: daniel.kruegler@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b="ibBhXm/n"; spf=pass (google.com: domain of daniel.kruegler@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=daniel.kruegler@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE 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:41552 Archived-At: Am Di., 12. M=C3=A4rz 2019 um 19:17 Uhr schrieb : > > The one thing that has irritated me the most with the standard library is= using ::empty() instead of ::is_empty(). Is there a possibility of adding = is_empty() to every class using empty()? > I don't consider that as a viable option: 1) An API that provides both "empty" and "is_empty" is confusing: Does "empty" means something different? In addition: This is not really new functionality, it is just selling existing functionality under a new name. 2) Albeit the current Container requirements are actual tables that are intended to simplify the Standard C++ Library specification, many programmers in the world do consider them as kind of concepts and this means that you break existing libraries providing a "Standard Container" type which don't provide yet both empty() and is_empty() 3) Why should we modify a bunch of types in the standard, if we could just provide a single _free_ function template? Problem is: We already have such a single free function "empty" ;-) My recommendation is: Why don't you define your own free function template is_empty (similar to the free function "empty" as described by (3)) that delegates either to std::empty() or that implements an even simpler protocol (Such as that it participates in overload resolution when x.empty() is valid for some const object x of type X)? - Daniel --=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/CAGNvRgCNM%2B4kcz2hXOKh-z_oRzvt6ehZN%3D_4J%3Dxmo= D9CyBhO5w%40mail.gmail.com. .