c++ - template implements __uuidof
- nyra sohu.com (43/43) Feb 01 2005 I implements MSC++ keyword __uuid partly with template.
- Matthew (20/64) Feb 02 2005 COMSTL has had this for several years, in the form of its IID_traits<>
I implements MSC++ keyword __uuid partly with template. It May be usefull to port ATL and lastest MFC library to DMC++. The source code. #include <ole2.h> //for type REFIID ... template <typename T> struct UUID_Traits; #define DEFINE_IID_TRAITS(interface) \ template<> struct UUID_Traits<interface>\ {\ static REFIID GetIID()\ {\ }\ }; DEFINE_IID_TRAITS(IUnknown) DEFINE_IID_TRAITS(IDispatch) template <typename T> inline REFIID uuidof(T&) { return UUID_Traits<T>::GetIID(); } template <typename T> inline REFIID uuidof(T*) { return UUID_Traits<T>::GetIID(); } //-0------testing------0- #include <stdio.h> void print_iid(REFIID riid) { LPOLESTR test; StringFromCLSID(riid, &test); printf("%ws\n", test); CoTaskMemFree(test); } int main() { CoInitialize(0); IDispatch* p1; IUnknown& p = *p1; print_iid(uuidof(p)); print_iid(uuidof(p1)); CoUninitialize(); }
Feb 01 2005
COMSTL has had this for several years, in the form of its IID_traits<> class template, where it forms an integral part of the interface_cast<> mechanisms. It also resolves to using __uuidof on compilers that support it. See comstl_interface_cast.h, comstl_interface_traits.h & comstl_interface_traits_std.h The full technique's explained in detail in Chapter 19 of my book, Imperfect C++ (http://www.awprofessional.com/titles/0321228774/). Cheers Matthew Wilson Author: "Imperfect C++", Addison-Wesley, 2004 (http://www.imperfectcplusplus.com) Contributing editor, C/C++ Users Journal (http://www.synesis.com.au/articles.html#columns) STLSoft moderator (http://www.stlsoft.org) ------------------------------------------------------------------------------- "So far, C++ is the best language I've discovered to say what I want to say" -- Alex Stepanov ------------------------------------------------------------------------------- <nyra sohu.com> wrote in message news:ctpu8p$2bqr$1 digitaldaemon.com...I implements MSC++ keyword __uuid partly with template. It May be usefull to port ATL and lastest MFC library to DMC++. The source code. #include <ole2.h> //for type REFIID ... template <typename T> struct UUID_Traits; #define DEFINE_IID_TRAITS(interface) \ template<> struct UUID_Traits<interface>\ {\ static REFIID GetIID()\ {\ }\ }; DEFINE_IID_TRAITS(IUnknown) DEFINE_IID_TRAITS(IDispatch) template <typename T> inline REFIID uuidof(T&) { return UUID_Traits<T>::GetIID(); } template <typename T> inline REFIID uuidof(T*) { return UUID_Traits<T>::GetIID(); } //-0------testing------0- #include <stdio.h> void print_iid(REFIID riid) { LPOLESTR test; StringFromCLSID(riid, &test); printf("%ws\n", test); CoTaskMemFree(test); } int main() { CoInitialize(0); IDispatch* p1; IUnknown& p = *p1; print_iid(uuidof(p)); print_iid(uuidof(p1)); CoUninitialize(); }
Feb 02 2005