220 37313 article Path: news.gmane.org!.POSTED!not-for-mail From: Larry Evans Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Pointer overload for || Date: Mon, 12 Mar 2018 05:32:52 -0500 Lines: 45 Approved: news@gmane.org Message-ID: References: <1fea07df-46a6-4df2-865a-849be8f8d129@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed X-Trace: blaine.gmane.org 1520850660 31471 195.159.176.226 (12 Mar 2018 10:31:00 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 12 Mar 2018 10:31:00 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDAYTI72VMGRBXNOTHKQKGQERMXFNSA@isocpp.org Mon Mar 12 11:30:56 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-lf0-f72.google.com ([209.85.215.72]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1evKjH-00085i-Js for gclcip-std-proposals@m.gmane.org; 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Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1evKjE-00080j-9z for std-proposals@isocpp.org; Mon, 12 Mar 2018 11:30:52 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 38 Original-X-Complaints-To: usenet@blaine.gmane.org In-Reply-To: <1fea07df-46a6-4df2-865a-849be8f8d129@isocpp.org> Content-Language: en-US X-Original-Sender: cppljevans@suddenlink.net X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 195.159.176.226 is neither permitted nor denied by best guess record for domain of gclcip-std-proposals@m.gmane.org) smtp.mailfrom=gclcip-std-proposals@m.gmane.org Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org 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:37313 Archived-At: On 03/11/2018 03:38 AM, jeffersoncarpenter2@gmail.com wrote: > Not sure how this will be received -- I haven't posted here much. Just > thought it would be worth mentioning this idea. > > Suppose you have an API that you want to optionally allocate storage for > your user. They can either pass in a pointer to some existing allocated > space, or pass in a null pointer and space is allocated for them. > > void foo(int *x) { > if (x == nullptr) { > x = new int; > } > // etc. > } > > Just figured it would be a decent idea if the || operator received a > pointer overload. Then you could write the more succinct > > void foo(int *x) { > x = x || new int; > } > > or even (ducks for cover) > > void foo(int *x) { > x ||= new int; > } > > would be nice. > There's precedent in another language, ruby. An example use is: https://github.com/tardate/pdf-reader-turtletext/blob/master/lib/pdf/reader/positional_text_receiver.rb#L16 with explanation here: http://www.rubyinside.com/what-rubys-double-pipe-or-equals-really-does-5488.html -- 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 email 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/p85ksl%24tij%241%40blaine.gmane.org. .