John Goerzen jgoerzen at
Fri Mar 31 16:59:41 EST 2006

On Fri, Mar 31, 2006 at 01:51:14PM -0800, John Meacham wrote:
> > If so, we should specify what exception is raised if, say, forkIO is
> > called on such a system.  We should also make it clear that
> > single-threaded implementations are required of things such as MVars.
> > Finally, we should add a function that indicates the level of threading
> > support on the running system.
> routines that are guarenteed to fail becaues they arn't supported should
> not exist, haskell tries hard to catch so many errors at compile time,
> it would seem odd to delegate the error of missing a whole subsystem to
> run-time :) 

Not really.  What if I'm writing a program that can take advantage of
threading if it's available, but can degrade gracefully if not?  Should
I be forced to use something like cpphs to detect the presence of
threading in advance?  It would be better to detect this at runtime than
fail to compile at all on a system that doesn't support threading, IMHO.

-- John

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