ForeignPtr

[Ross Paterson]

On Thu, Nov 07, 2002 at 04:53:04PM +0000, Alastair Reid wrote:
> 
> >> On first glance, this looks cool.  What instances do you envision
> >> (assuming I persuaded you that StablePtr and FunPtr should not be)?
> 
> > How about Int (for file descriptors, etc)?
> 
> Ah, got you.
> 
> How about making ForeignPtr slightly more polymorphic so that instead of
> working only on 'Ptr a' it works on 'a'.

That was Ashley's original proposal, but SimonM responded in

http://www.haskell.org/pipermail/glasgow-haskell-users/2001-September/002290.html
http://www.haskell.org/pipermail/glasgow-haskell-users/2001-September/002304.html

that the extra boxing was unsafe in GHC.  Hence the Finalizable class
for boxed primitive objects, similar to the way UArray's are presented
without exposing GHC's unboxed types.