220 1448 <738f626c-3b23-4c74-9eea-2c2246921a81@isocpp.org> article Path: news.gmane.org!not-for-mail From: Arthur Tchaikovsky Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: making using declaration more precise Date: Sat, 5 Jan 2013 10:07:03 -0800 (PST) Lines: 89 Approved: news@gmane.org Message-ID: <738f626c-3b23-4c74-9eea-2c2246921a81@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_1718_9219898.1357409223686" X-Trace: ger.gmane.org 1357409228 21253 80.91.229.3 (5 Jan 2013 18:07:08 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 5 Jan 2013 18:07:08 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDL6FI4NYYERBSWXUGDQKGQE46JWWOY@isocpp.org Sat Jan 05 19:07:25 2013 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-vb0-f69.google.com ([209.85.212.69]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1TrY9S-0004lR-Vx for gclcip-std-proposals@m.gmane.org; Sat, 05 Jan 2013 19:07:23 +0100 Original-Received: by mail-vb0-f69.google.com with SMTP id ff20sf26886871vbb.8 for ; Sat, 05 Jan 2013 10:07:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:x-beenthere:x-received:date:from:to:message-id:subject :mime-version:x-original-sender:reply-to:precedence:mailing-list :list-id:x-google-group-id:list-post:list-help:list-archive :list-subscribe:list-unsubscribe:content-type; bh=TddBTv+9sQo60rAebC6ycchtvVu3pPtYDQc69O5uFlA=; b=n7srmI4cfbSgq1Hb9Ncz8GM9NhV5l4MpHQu4vXKBCVLJlwSzMQhmSUc4IjPe95ABYa 46zBChmbo2rQbRB69pdWPY3XZLY4KOaEqHvCUr7kfpVZgkMX0Q8ohSlY4jszJ2+fBYkd 7hQep8O3uAKX1T6qOshmEK6chJ/12dPckhhsG7L+og8WtqrtEgy30QQUMBSx+rztcrhs 6NjBIDZrnYLS9+U+ZLaZWdwNVnZLvs04DFHnEUBaQVd4QDkq8ZFBgmh0zGDejqnKxIeg qLstO28KFrNLoKmzPpI/Y829lbKe+itvwyVGjm+UBo5xyD7GdeUzJz0tpYpr1rCdwoJq UkRA== X-Received: by 10.224.207.66 with SMTP id fx2mr32763288qab.7.1357409226968; Sat, 05 Jan 2013 10:07:06 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.49.0.19 with SMTP id 19ls7573983qea.55.gmail; Sat, 05 Jan 2013 10:07:05 -0800 (PST) X-Received: by 10.49.48.41 with SMTP id i9mr9510243qen.36.1357409225026; Sat, 05 Jan 2013 10:07:05 -0800 (PST) X-Original-Sender: atch.cpp@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:1448 Archived-At: ------=_Part_1718_9219898.1357409223686 Content-Type: text/plain; charset=ISO-8859-1 I wonder if anyone feels the same as me about using declaration while specifying members from base class? As things are now, it is very blunt and not very precise tool, which could be quite easily tweaked. What I mean is: class A { public: void f(); void f(int); }; class B: public A { using A::f;//here we cannot make a choice on which one we would like to use in our B class, which sometimes is ok... }; but in scenario: class A { void f(int); public: void f(); }; class B :public A { using A::f;//will not compile even though the only fnc we want is A::f() }; What I would like to propose is following backwards compatible syntax: class B :public A { using A::f;//here I'm specifying that I want use every fnc 'f' from A - just like before, but this will not compile using A::f();//here I explicitly specify which fnc I want to use }; The use case which is I believe compelling is the one that if function f overloaded and one or more is declared private, this actively prohibits us from the use of any other, non-private functions 'f' from the base class. Looking forward to comments. -- ------=_Part_1718_9219898.1357409223686 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable I wonder if anyone feels the same as me about using declaration while speci= fying members from base class? As things are now, it is very blunt and not = very precise tool, which could be quite easily tweaked.
What I mean is:=

class A
{
public:
v= oid f();
void f(int);
};

c= lass B: public A
{
using A::f;//here we cannot make a c= hoice on which one we would like to use in our B class, which sometimes is = ok...
};

but in scenario:
clas= s A
{
void f(int);
public:
void f()= ;
};

class B :public A
{
=
using A::f;//will not compile even though the only fnc we want is A::f= ()
};

What I would like to propose is fo= llowing backwards compatible syntax:

class B = :public A
{
using A::f;//here I'm specifying that I wan= t use every fnc 'f' from A - just like before, but this will not compile
using A::f();//here I explicitly specify which fnc I want to use
};

The use case which is I believe&n= bsp;compelling is the one that if function f overloaded and one or more is = declared  private, this actively prohibits us from the use of any= other, non-private functions 'f' from the base class.

=
Looking forward to comments.

--
 
 
 
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