Re: Using policy based design with Singleton template class
Is there any elegant way for a class to derive from a template
singleton class (e.g. Meyer's singleton) yet still allow for
flexibility via policies? That is, what I want to do is something like
template <template <typename> class MyPolicy>
: public Singleton<Foo>
, public MyPolicy<Foo>
It would be nice to have allow clients the flexibility that comes with
policies, yet to be able to enforce uniqueness through the singleton
design. I am unable to come up with a simple solution that doesn't
have any loop holes.
Alexandrescu discusses this somewhat in Modern C++ Design.
I don't have the book handy, but I think it's something like:
// policy interface
template<typename T, typename Policy = DefaultPolicy>
// Singleton interface
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