Hello Günther,
I use ContT monads for early exit often, because that's one of the
things they encode naturally. But I don't do this with callCC. I
prefer monadLib over mtl/transformers, which has a specific function for
that:
abort :: (AbortM m i) => i -> m a
where AbortM is a class for monads, whose computations are abortable.
All ContT monads are instances. This is also a nice way to break out of
'forever'.
Using an error monad (like Maybe) may be more natural of course.
Greets,
Ertugrul
Günther Schmidt
Hi everyone,
I'm about to write a rather lengthy piece of IO code. Depending on the results of some of the IO actions I'd like the computation to stop right there and then.
Now I know in general how to write this but I'm wondering if this is one of those occasions where I should make use of the Cont monad to make an early exit.
Günther
-- nightmare = unsafePerformIO (getWrongWife >>= sex) http://blog.ertes.de/