C++Talk.NET C++ language newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  specialized constructor of templated class          C++Talk.NET Forum Index -> C++ Language (Moderated) View previous topic :: View next topic   Author Message Guest Posted: Mon Aug 07, 2006 4:35 am    Post subject: specialized constructor of templated class Hi there, is this standard complaint code? My compiler (VC 7.1) gives me an error (C2931). But, when searching the groups I could see that other compiler swallow that. template< class T > class pixel_t { public: pixel_t() : _nRed ( 0 ) , _nGreen( 0 ) , _nBlue ( 0 ) {} template< > pixel_t<float>() : _nRed ( 0.f ) , _nGreen( 0.f ) , _nBlue ( 0.f ) {} }; Thanks ahead, Christian [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.moderated. First time posters: Do this! ] Back to top Greg Herlihy Guest Posted: Mon Aug 07, 2006 8:24 am    Post subject: Re: specialized constructor of templated class chhenning (AT) gmail (DOT) com wrote: Quote: Hi there, is this standard complaint code? My compiler (VC 7.1) gives me an error (C2931). But, when searching the groups I could see that other compiler swallow that. template< class T class pixel_t { public: pixel_t() : _nRed ( 0 ) , _nGreen( 0 ) , _nBlue ( 0 ) {} template< > pixel_t<float>() : _nRed ( 0.f ) , _nGreen( 0.f ) , _nBlue ( 0.f ) {} }; VC 7.1 is correct: a member function of a template class cannot be specialized within the general class template. The solution is to move pixel_t<float>'s specialized constructor outside of the pixel_t class template declaration: template <> pixel_t<float>::pixel_t() : _nRed ( 0.f ), _nGreen( 0.f ), _nBlue ( 0.f ) { ... } Greg [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.moderated. First time posters: Do this! ] Back to top Guest Posted: Mon Aug 07, 2006 8:27 am    Post subject: Re: specialized constructor of templated class { Please remove the banner from the quotation, unless relevant. -mod } chhenning (AT) gmail (DOT) com wrote: Quote: Hi there, is this standard complaint code? My compiler (VC 7.1) gives me an error (C2931). But, when searching the groups I could see that other compiler swallow that. template< class T class pixel_t { public: pixel_t() : _nRed ( 0 ) , _nGreen( 0 ) , _nBlue ( 0 ) {} template< > pixel_t<float>() : _nRed ( 0.f ) , _nGreen( 0.f ) , _nBlue ( 0.f ) {} }; Thanks ahead, Christian { Banner stripped. -mod } I cannot compile your above code under gcc4.0 and I can only definite a specilaized constructor outside the class declaration like this: template<> pixel<float>::pixel_t() :_nRed(0.1f) ,_nGreen(0.1f) ,_nBlue(0.1f) {} [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.moderated. First time posters: Do this! ] Back to top Hrayr BABAJANYAN Guest Posted: Mon Aug 07, 2006 9:10 am    Post subject: Re: specialized constructor of templated class Hi, chhenning (AT) gmail (DOT) com wrote: Quote: Hi there, is this standard complaint code? My compiler (VC 7.1) gives me an error (C2931). But, when searching the groups I could see that other compiler swallow that. template< class T class pixel_t { public: pixel_t() : _nRed ( 0 ) , _nGreen( 0 ) , _nBlue ( 0 ) {} template< > pixel_t<float>() : _nRed ( 0.f ) , _nGreen( 0.f ) , _nBlue ( 0.f ) {} }; Thanks ahead, Christian The "full" specialization of the member function of class template should be declared/defined in the same namespace/scope as the class declarationd (outside the class). // >>> a.h template<typename T> class A { pubilc: void f(T); }; template<typename T> void A::<T>f(T) {} template<> void A<int>::f(int); // move definition to some cpp file to avoid liker errors... // <<< a.h // >>> a.cpp template<> void A<int>::f(int) { } // <<< a.cpp Cheers! -- Hrayr [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.moderated. First time posters: Do this! ] Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         C++Talk.NET Forum Index -> C++ Language (Moderated) All times are GMT Page 1 of 1   Jump to: Select a forum C/C++----------------C LanguageC Language (Moderated)C++ Language (Moderated)C++ language (comp.lang.c++)C++ language, library and standards Non-English C/C++ Newsgroups----------------C++ (German)C++ (French)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.