On Fri, Jul 9, 2010 at 7:16 AM, Emil Melnicov
writeTVector :: TVector a -> Int -> a -> STM () writeTVector (TVector t#) (I# i#) x = stm $ \s1# -> case readTVar# t# s1# of { (# s2#, (MutableArray a#) #) -> case writeArray# a# i# x s2# of { s3# -> case writeTVar# t# (MutableArray a#) s3# of { s4# -> (# s4#, () #) }}}
It seems like it works, but I'm in doubt about it's correctness. Unfortunately, I don't know much about STM mechanics, so I'm asking Cafe users (you :-) for help.
I guess the only problem lies with writeTVector. I don't know much about STM implementation details as well, but reading the code for writeTVector I can't see how it could be rollbacked. I.e., should something with writeTVector fail and rollback, how will the old value get into the mutable array? Cheers :) -- Felipe.