Sohail Somani wrote:
Thanks for your reply but the domain of COM objects lends itself well to shared_ptr.
As to scoped_ptr. I don't quite understand the "but" in that sentence.
I went through the archives after the posts and I have realized that scoped_ptr is not changing! I will still disagree that the deleter shouldn't be a parameterized type.
What's wrong with: template<typename T> void free_resource(T* ptr) { delete ptr; } void free_resource(std::FILE* f) { std::fclose(f); } void free_resource(IDispatch * o) { o->Release(); } template<typename T> struct scoped_ptr { // [...] ~scoped_ptr() { free_resource(this->p_); } // [...] }; ?! Adding another dummy parameter will make ADL work (see attached file for demonstration of the technique).
The only other option is using a type erasure mechanism like shared_ptr which is more trouble than its worth for things like deallocating C resources.
I was referring to the file pointer, which is pretty much the only "C resource" I use. You're right when it comes to malloc/free, of course - but do we really need it? Regards, Tobias #include <iostream> namespace framework { enum adl_hook { use_adl }; template<typename T> inline void visit(T const & o, adl_hook) { std::cout << "default case" << std::endl; } } namespace my_prj { struct my_class { }; void visit(my_class const & x, framework::adl_hook) { std::printf("my_class\n"); } } int main() { int a = 1; my_prj::my_class b; visit(a, framework::use_adl); visit(b, framework::use_adl); return 0; }