Re: fixIO

Malcolm Wallace <[email protected]> Tue, 2 Sep 2003 16:32:25 +0100

Newsgroups	gmane.comp.lang.haskell.nhc.bugs
Organization	Dept of Computer Science, University of York
Message-ID	<[email protected]>

Ross Paterson <[email protected]> writes:

> The definition of fixIO used by Nhc (in System.IO), namely
> 	fixIO f = let x = unsafePerformIO (f x) in return x
> produces the wrong results.  I suggest: 
> 	fixIO f = IO (\w -> let { IO f' = f a; r = f' w; Right a = r } in r)

Thanks for the bug report and the fix, now committed.

Regards,
    Malcolm