Asynchronous exceptions in haskell

Asynchronous exceptions, such as timeouts, are important for-robust, modula r programs, but are extremely difficult to program with - so much so that m ost programming languages either heavily restrict them or ban them altogeth er. We extend our earlier work, in which we added synchronous exceptions to Haskell, to support asynchronous exceptions too. Our design introduces sco ped combinators for blocking and unblocking asynchronous interrupts, along with a somewhat surprising semantics for operations that can suspend. Uniqu ely, we also give a formal semantics for our system.