On Sat, 2009-12-26 at 23:11 -0600, Floptical Logic wrote:
Hi,
I am new to concurrency in Haskell and I am having trouble implementing the notion of interrupting a thread.
In a new thread, call it waitNotify, I am trying to do the following: pop a number from a stack, wait some number of seconds based on the number popped from the stack, perform some notification, and repeat until there are no more numbers in the stack at which point we wait for a new number.
These numbers will be supplied interactively by the user from main. When the user supplies a new number, I want to interrupt whatever waiting is happening in waitNotify, insert the number in the proper position in the current stack, and resume waitNotify using the updated stack. Note, here "stack" is just a generalization; it will likely just be a list.
What is the most idiomatic way to capture this sort of behavior in Haskell? My two challenges are the notion of interrupting a thread, and sharing and updating this stack between threads (main and waitNotify).
Thank you
1. Hmm. IMHO - maybe you should look on CHP. As far as I remeber writing/reading to channel there is blocking. 2. You mean stack (FILO) or queue (FIFO)? 3. Why don't just read lazily from input? Regards