[Haskell-cafe] ANNOUNCE: New versions of ALL the monadic regions packages

Felipe Lessa felipe.lessa at gmail.com
Thu Jan 7 11:15:45 EST 2010

On Thu, Jan 07, 2010 at 04:00:31PM +0100, Bas van Dijk wrote:
> As I explained in my announcement of 'safer-file-handles', I
> discovered a serious lack of expressive power in my 'regions' package.
> I have now solved that problem in the way I envisaged by removing the
> 'resource' parameter from 'RegionT' and using existential
> quantification to bring the 'resource' type back at the place I need
> it but hidden from the outside.

But if I understand correctly, now you can't know from the type
signature what kind of resource a given code accesses.  Isn't
this a drawback?  Wouldn't it be better to write something like

  TopRegion (File `And` Network)

to tell something needs both?



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