Robert Dockins
So, to be safe, the action of a finalizer must commute with every other finalizer (they must be central).
What does "should" mean? There are useful finalizers which don't have this property. E.g. a finalizer can remove an entry from a weak dictionary, call a C function which will free some foreign object, or send a message over a network that a particular object is no longer needed. Even if they have these properties in an abstract sense, they are not true technically.
So a separate ACIO monad for affine central IO actions would be the appropriate context for finalizers.
It would not be enough without unsafeIOtoACIO. -- __("< Marcin Kowalczyk \__/ qrczak@knm.org.pl ^^ http://qrnik.knm.org.pl/~qrczak/