Ashley Yakeley wrote:
Adrian Hey wrote:
Maybe it would be safest to just say anything with a finaliser can't be created at the top level.
Do you have an example of something that is correctly ACIO to create, but has a problematic finaliser?
Sorry for the delay in getting my attention. I've been looking at my old ACIO code (which I've largely forgotten the details of) and dug up the following snippet. -- * Weak pointers -- | All these functions require that finalisers (if any) are in the -- ACIO Monad. -- I'm not sure what such a finaliser can usefully do, but it can't be -- in the IO Monad and preserve ACIO Monad properties AFAICS. mkWeak,mkWeakPtr,mkWeakPair,addFinalizer,mkWeakIORef, I must admit I can't remember much about any of this, I just worked my way through the IO libs trying to figure out which actions might plausibly (if not usefully :-) be regarded as ACIO. There seemed to be quite a lot at the end of the day. I also added a few forkIO variants which force the forked thread to block on certain things (empty MVar,Chan, QSem..) waiting for some IO monad action to kick them into life. Regards -- Adrian Hey