unsafePerformIO and unsafeInterleaveIO

[Simon Marlow]

> > Without a standard way to get
> > at unsafePerformIO, such code would still rely on
> > non-standard features, which goers against the aim of
> > standardising the rest of the FFI.
> 
> The Hugs-GHC standard libs have them exported from IOExts.
> 
> Of course, the Hugs-GHC standard isn't an official Haskell 
> library committee approved standard but, since it's something like 4
> years old, I think it's a better candidate for approval than 
> the ffi library which hasn't really stabilised yet, hasn't 
> been whacked
> on by a large number of users, is much younger, etc.

Sadly, due to lack of support on the Hugs side, the Hugs/GHC extension
libraries have drifted apart.  I would have liked Hugs to ship with a
cut-down hslibs at some point (and indeed there's some support in the
hslibs build system for Hugs), but there was no-one available at the
Hugs end to do the work and make it happen.

Longer term, the effort currently underway on libraries at haskell.org
should eventually provide a unified story for "extension" libraries.

Cheers,
	Simon