From: Jason Hise <chaos@ezequal.com>
Pavel Vozenilek wrote:
The use case is a legacy code that accepts only bald pointer.
A singleton may have function unsafe_get(). The object would be instantiated if not already.
Code using its result will promise not to destroy given object.
In such cases, I wonder if it might be best for the user's singleton to provide the function:
class Example : public singleton < Example > { // protected ctor and dtor public: Example * unsafe_get ( ) { return this; } };
That way not all singleons would need to suffer the 'security hole' just because a few need it.
That's definitely better. You don't want to make it pretty when someone adds this feature. However, given that the need for this behavior might be just common enough to make this addition to every Singleton type too much pain, how about another class template: template <typename T> class unsafe_singleton : public singleton<T> { public: //! WARNING: Do not delete the returned pointer! T * unsafe_get() { return this; } }; -- Rob Stewart stewart@sig.com Software Engineer http://www.sig.com Susquehanna International Group, LLP using std::disclaimer;