Article View: comp.std.c++
Article #3996Re: Ambiguity when overloading operators
From: Steve Clamage
Date: Fri, 12 Apr 1996 07:33
Date: Fri, 12 Apr 1996 07:33
32 lines
1659 bytes
1659 bytes
In article 1@CompuServe.COM, Martin Aupperle <100754.2730@CompuServe.COM> write
s:
> struct X {
> X( int );
> operator const char* () const;
> };
> X& operator + ( const X&, const X& );
>I cannot say
> X x1( 5 );
> X x2 = x1+3; // ambiguous
>Borland BC4.5 says that x1+3 is ambiguous. I know that it can
>1. convert 3 to an X and call operator + ( const X&, constX& )
>2. convert x1 to a const char* and do pointer arithmetics.
Yes. Each choice involves exactly one user-defined conversion,
and no user-defined conversion is preferred over any other.
The compiler is correct.
---
Steve Clamage, stephen.clamage@eng.sun.com
---
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From: clamage@Eng.Sun.COM (Steve Clamage) Message-ID: <4kkam3$dg8@engnews1.Eng.Sun.COM> X-Original-Date: 12 Apr 1996 01:12:35 GMT Path: arc1-ca.pugleaf.net!in2.uu.net!bounce-back Date: 12 Apr 96 07:33:34 GMT Approved: fjh@cs.mu.oz.au Newsgroups: comp.std.c++ Subject: Re: Ambiguity when overloading operators Organization: Sun Microsystems Inc. References: <960411233436_100754.2730_GHV68-1@CompuServe.COM> Reply-To: clamage@Eng.Sun.COM X-Auth: PGPMoose V1.1 PGP comp.std.c++ iQBFAgUBMW4ODuEDnX0m9pzZAQELVwF+IhLm/RdkxpBRCKZbi/G2nsAYHl2GuO+w F9hVzl2nOVmZ/HHYWkezoV2E8DYc4B1U =mF1V