-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thursday 09 July 2009, Andrey Semashev wrote:
Frank Mori Hess wrote:
I wonder if it might be better/possible to have a shared_ptr<T> that didn't assume its corresponding "raw" pointer type was T* but rather T. For example, what is now a shared_ptr<int> would be specified as a shared_ptr<int*>. The motivation would be to allow support for other classes as the "raw" pointer type. For example, I might want to have a shared_ptr<monitor<T*> > where the monitor<T*> has an operator->() which does automatic locking/unlocking of a mutex before/after forwarding the operator->() to the plain T pointer.
Why not having monitor_ptr< T > contain the shared_ptr and implement operator-> the way you described?
Yes, that is in fact what I did: http://www.comedi.org/projects/libpoet/boostbook/doc/boostbook/html/poet/mon... However, it seems like more work to have to provide a full shared_ptr interface, than to implement a plain pointer interface. And perhaps more significantly, a monitor_ptr is a completely different type than a shared_ptr. So, for example, a monitor_ptr can't be passed to a function that expects a shared_ptr as an argument. Also, if there are other applications for pointer wrapper classes, they could be mixed an matched in any combination by the end user in this scheme, like shared_ptr<monitor<pointer_wrapper<T*> > > Maybe, for example, a pointer wrapper class might enforce that the wrapped pointer may never be NULL, to implement a shared_ptr that acts something like a "smart reference". -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkpWLu4ACgkQ5vihyNWuA4WFAgCgj2hnsj5uZs1R78+YI2UVVLz0 0tYAoKLA67xb4pgNJXSkr9XbO+Hi7pcH =2OvX -----END PGP SIGNATURE-----