Thank you all, I've used a simple IORef and that did the trick.
JP
2012/2/8 Edward Amsden eca7...@cs.rit.edu:
If you only need one structure for communication (e.g. neither thread
needs to lock multiple things) you might consider using an IORef, and
writing/polling it with atomicModifyIORef.
Hello, I'm wondering what's the best strategy to use in the following scenario:
- 2 threads
- One perform some work that will take time, possibly go on forever
- Another waits for user input (like commands from the keyboard)
that affects thread 1 (causing it to stop, in the simplest case)
You could use throwTo to raise an exception in the thread you want to
stop. Otherwise, having some variable (IORef, TVar, MVar) that the
long running thread occasionally checks seems like a good solution.
Erik
On Wed, Feb 8, 2012 at 17:04, JP Moresmau jpmores...@gmail.com wrote:
Hello, I'm
Why do you think it's a lot? MVar are a teeny tiny and convenient primitive
of communication, and I don't see why they wouldn't suit your need.
Sure a throwTo would do the trick... But they're is do the trick and do
the job, you see?
Using STM and TVars *would* be kind of overkill.
2012/2/8 JP
No, I meant they seem to be mainly for the use case where the reading
thread blocks for more input, and maybe there's a simpler/more
efficient way to quickly check if an event has occurred, that's all.
If there isn't then a MVar it will be.
JP
On Wed, Feb 8, 2012 at 7:35 PM, Yves Parès
If you only need one structure for communication (e.g. neither thread
needs to lock multiple things) you might consider using an IORef, and
writing/polling it with atomicModifyIORef. It's cheaper than an MVar
for the case where you don't need to lock multiple threads.
On Wed, Feb 8, 2012 at 2:45
